There have been other steampunk Avengers, but with the Hulk in suspenders and a bowler? I'd read a comic just about him.
Anyway, Brian Kesinger is awesome and you should check out his blog and DeviantArt page. He also does steampunk other things, like Transformers, G.I. Joe, and Star Wars. But if steampunk's not your thing, his Hip Hop Boba Fett and Pooh vs. Voldemort are cool, too. I posted bunch of my favorites below.