Etsy seller EwoksInTutus has designed a Worf-inspired hooded sweatshirt that makes use of more than his warrior's sash. If you pull up the hood, you get a nice bit of lazy cosplay in the form of his Klingon forehead ridges. Now we need a Deep Space Nine version, too.
The hoodies are $95 and available from Etsy, via Geeks are Sexy. As a lot of commenters below have noted, the ridges could use a bit of work. Perhaps we'll see other makers try something on the same theme.