This is a steampunk Samus Aran arm cannon made by DeviantARTist Skinz-N-Hydes (NOT Skinz-N-Shirtz, which is how you play kickball). Whether you're into steampunk stuff or not, you've got to admit it would suck to sit on bare-assed. "No it wouldn't." Haha, I know.
Hit the jump for a couple more pics, as well as some of his 'Glove-O-Love' steampunk arm made for a film short, but be sure to check out his DeviantART page for a ton more of steapunkery if you're into it.