When you really want to show people you care about them, the best present is one that they can spend hours exploring. And nothing sucks people in quite like a really feature-heavy DVD or Blu-ray box set, full of special features, alternate versions and commentary tracks.

There's an amazing wealth of science fiction and fantasy stuff available on DVD lately, so there are tons of great gift ideas to choose from. We've combed through a ton of releases, and here's our list of 20 scifi/fantasy box sets that make amazing gifts — ranked from the cheapest to the most expensive.

Four Schlock Horror Films for $4
At least, that's what this box set should be called. It features the all-time classics Severed, Carnivore, Children of the Living Dead, and Creep. Not exactly the fanciest gift, but there's a solid evening or two of entertainment in here, and I must confess I'm a bit curious to find out how the living dead managed to procreate. Also available are Dracula: Dark Prince/Frost/Premonition/Hell's Gate, and this awesome collection.
Price: As low as $4 on Amazon.

Captain America/Captain America II: Death Too Soon Double Feature
Sure, you could get the recent Captain America film on DVD, or the 1990 Albert Pyun version. But Shout Factory! has a two-DVD set of the 1979 TV movies, in which Steve Rogers wears a goofy motorcycle helmet with Captain America's insignia on it. Watch Steve Rogers, former Marine and struggling artist, get an injection of the FLAG formula, for extra patriotism! This version is guaranteed to have more disco and motorcycles than any other.
Price: $13.98.

Tremors Attack Pack!
The classic original Tremors, starring Kevin Bacon, gets packaged with all three sequels in an ultra-cheap box set. You couldn't really hope for more subterranean monster rampage. Plus there are tons of making-of featurettes, especially for the first and third movies.
Price: $14.98.

Gamera - Triple Feature Collector's Edition
All three 1990s Gamera movies are collected in one two-disc Blu-Ray set, complete with a ton of extras like camera tests, deleted scenes and location footage — although apparently the extras are just one big standard-def feature, with chapter breaks and inaccurate labeling. This is probably your best, and cheapest, opportunity to get all three installments in this attempt to relaunch Gamera as a serious franchise from Death Note's Shusuke Kanedo. Giant turtle action has never been more awesome.
Price: $20 but you can get it for under $10 on Amazon.

A Big Box of Vampires
Eight vampire movies that you've probably never heard of, dating from 1932 to 1970 — probably a pretty fascinating tour through vampire lore. Probably worth getting just for The Nude Vampire — watch the trailer for that film at left, complete with bongo dancing and weird fang-shaped pasties, not to mention matching windchime dresses. (Honestly, do yourself a favor and watch that trailer now, it's amazeballs.) But then you get seven other films, which might be equally as nuts.
Price: $20, but you can get it for around $10 on Amazon.

Zombie Triple-Feature
A collection of three Japanese cult zombie movies, with the word "NIHOMBIE!" scrawled across the bottom. Includes Attack Girls' Swimteam Vs. The Undead, in case you really wanted to see swimmers with chainsaws. Plus Zombie Self-Defense Force and Zombie Hunter Rika. Will it include zombie body-part sushi? We can only hope.
Price: $20, but available cheaper on Amazon.

Trancers: The Ultimate Deth Collection
If you're not familiar with the Trancers movie series, you could kill a fun weekend watching this set — in the first movie, Jack Deth travels back in time from the 22nd century to stop a supervillain who uses mind control on people, and saves Helen Hunt from certain death. In the four sequels, Jack Deth stops more time-traveling "Trancer" supervillains, and eventually returns to the future — and even travels to an alternate universe where magic is real and Trancers rule the Earth. I think Helen Hunt is only in the first one, though.
Price: $30, although I'm sure you can find it cheaper.

Dark Skies: The Declassified Complete Series
This X-Files-esque show about a man and a woman investigating secret aliens connected to the 1947 Roswell crash only lasted one season... but it had its definite high points, and it's fun to watch another take on the paranoid conspiracy-theory genre. This complete box set includes the original sales presentation, a ton of featurettes, and the creators' pitch for an unmade second season.
Price: $34.45.

Blue Gender - The Complete Series and Movie
Relive the anime series and the movie that followed, about alien insects that take over the Earth and drive humanity onto another planet. Relive the battle to retake our planet! Includes extended versions of some episodes, Japanese commercials, and a collection of rough sketches, plus some other stuff.
Price: $39.98.

Transformers: The Complete Original Series
There are tons of Transformers box sets out there right now, including Beast Wars and Headmasters — but the original mid-1980s series is still the greatest. This box set includes all 98 episodes of the original G1 animated series — plus wacky extras like the Transformers PSAs.
Price: $59.99.

Jem and the Holograms - the Truly Outrageous Complete Series
This awesome animated series is finally out on DVD in its entirety, and that means you can relive the adventures of Jerrica Benton and her alter ego, pop legend JEM. We interviewed voice actor Samantha Newark a while back, and she told us, "It was pretty progressive, right? We didn't use magic, we used science. But then again there was this magical chemistry between all the girls."
Price: $59.99

Jurassic Park Ultimate Trilogy
This is probably the best package of all three Jurassic Park films so far, including a nice remastered Blu-ray set. The Blu-rays include the original featurettes on the making of all three films, plus new making-of featurettes. And there's a new six-part documentary called Return to Jurassic Park. If you've been wanting to relive the movies that proved CG creatures could be realistic and get some dinosaur mayhem, this is a great chance.
Price: $80 on Blu-ray, $50 on DVD.

Robotech: The Complete Original Series
All 85 episodes of this series, including THE MACROSS SAGA, THE ROBOTECH MASTERS and THE NEW GENERATION, are collected in one remastered, deluxe box set. Including alternate versions of some episodes, that have never been released on DVD before. And the original Macross pilot, plus music videos and some supplemental materials from the Robotech movie. There's also a Making of Robotech documentary, so you can learn just how three unrelated anime series were edited into one show for U.S. audiences. According to Amazon reviewers, this is the best packaging of the Robotech series yet, and a great gift for the nostalgic anime fan in your life.
Price: $100 but available for around $60.

Lord of the Rings: The Motion Picture Trilogy: Extended Editions on Blu-ray
This insane 15-disc set came out last June, so chances are a lot of people already have it — but that also means it's probably a lot more affordable by now. And by all accounts, it's a monster, with five discs for each of the three movies. Fans who were upset when the 2010 Blu-ray releases only included the theatrical cuts of the three Peter Jackson films should be satisfied with these definitive releases of the full-length extended versions. Each film gets two Blu-ray discs for full picture quality, plus three DVDs containing appendices and a making-of documentary. The review over at Blu-ray.com is pretty encouraging.
Price: $120, but I bet you can find it way cheaper by now.

Superman: The Motion Picture Anthology on Blu-ray
Another box set that came out last June — this collection includes all four Christopher Reeve films, plus the 2006 sequel Superman Returns. By all accounts, this is a pretty well done collection, with decent picture and sound (except for Superman Returns.) You can delve into just how it was that one of the most successful movie series was driven into the ground so relentlessly, by watching the theatrical cuts of the first two movies and then the extended and/or director's cuts. There are also tons of featurettes and interviews, as well as related materials like the 1951 movie Superman and the Mole Men and some cartoons. Oh, and Christopher Reeve's 1977 screen tests!
Price: $120 but it's widely available for half price.

Star Wars: The Complete Saga on Blu-ray
This Blu-ray set is, umm... controversial, but we had to include it. Chances are, any superfans of that galaxy far, far away already have this box set, but you probably have a friend or relative who doesn't own it yet — and he or she probably doesn't care that Darth Vader now says "noooo" or that the Ewoks are blinking. The bottom line is, you can get the original trilogy, plus those other movies they made, in one nice package, with crisp beautiful remastered picture quality. And tons and tons of deleted scenes that weren't available elsewhere. There are also some featurettes, and some audio commentaries.
Price: $140, but you know every local used DVD store will have copies from people who bought it and watched it once.

Harry Potter: The Complete Collection Years 1-7
Let's be clear — this is kind of a bare-bones DVD or Blu-ray set of all eight Harry Potter movies, and everybody's convinced that a more deluxe set is coming next year. On the other hand, you do get all eight movies in one set, and they include a few nice extras including deleted scenes from the final two films. This could be a nice gift for your friend who's read the books but resisted checking out the films. Plus this set is probably a lot cheaper than the deluxe version will be, and you (or your loved ones) can have it now.
Price: $140 on Blu-ray, $100 on DVD — although you can get them way cheaper.

Farscape: The Complete Series (Blu-Ray)
A complete box set of Farscape (minus the Peacekeeper Wars miniseries) has been out for a couple of years, but the Blu-ray set just came out yesterday. (And it's currently half price on Amazon.) As far as I can tell, the Blu-ray has exactly the same content and special features as the DVD version, it's just (hopefully) remastered in high-definition. The product description boasts of "unmatched sound and picture quality," which sounds nice.
Price: $200 but around $97 on Amazon.

Doctor Who: The Complete David Tennant Years
Sure, we all love Matt Smith as the Doctor, that ageless time traveler with a messiah complex. But David Tennant still has a special place in our hearts, and now you can turn all of your friends into Tennant fanatics, with this lovely box set. It's all three seasons of Tennant's run as the Doctor, plus the 2009 specials and the two animated stories. Some Amazon reviewers claim they've had trouble getting their discs out of the packaging, but apparently that's not true for most people. And people praise the lavishness of the packaging. (There's also Torchwood: The Complete Original UK Series, and Doctor Who: The Complete Sixth Series.)
Price: $199, but Amazon often has it for around $100.

Smallville: The Complete Series
Your friends can kill a lot of time watching ten seasons of Smallville — from the early Dawson's Creek-y years full of random "meteor freaks," to the later spandex orgy, in which every random DC Comics character had to make a cameo. This is probably the longest running superhero show of all time (depending how you define "superhero," I guess) and there's enough raw goofiness here to keep you entertained for weeks. The set doesn't come out until Nov. 29, so you'd have to pre-order it.
Price: $339.88, but Amazon has it for under $200.