Artist Benton Jew has worked on not one but three Hulk movie projects: Ang Lee's Hulk, Louis Leterrier's The Incredible Hulk, and a never-made film that with a script by Jonathan Hensleigh. Jew has shared artwork he created for those projects, including a mockup of Billy Crudup as Ang Lee's hulk.
Hensleigh's script had Bruce Banner, for some reason, injecting convicts with gamma-irradiated insect DNA, transforming them into fearsome insect men. In 1997, Industrial Light and Magic was hoping to work on the film, and Jew, who was working there at the time, drew what the Hulk might look like, battling those insect men (and what appears to be a giant humming bird):
He also developed Hulk designs, including the expression chart above and the Hulk design below:
Billy Crudup was originally slated to play Bruce Banner in Ang Lee's Hulk, and Jew created a Photoshop of what Crudup might look like as the transformed Hulk:
He provided other concept pieces for Lee's movie as part of ILM's bid on the project. Although he hadn't seen the script at the time, he decided to paint the Hulk being chased by helicopters in the desert.
He also played with a version of the Hulk with more Neandertal facial features, saying, "My idea here being that Hulk should be to Banner, what a kitten is to a lion." (Although I think he meant that the other way around.)
You can see more of Jew's Hulk art, including his storyboards for The Incredible Hulk, on his blog.