I've been doing this "RPG Monster a Day" thing.
All these monsters are 2d, and can be used for old-school first person style combat or, anything really.
They're released under a Creative Commons licenses, basically you're free to use them in non-commercial things, and you can go wild as far as derivative works are concerned so long as you give other people the same right. Also you have to credit me if you use em'.
Anyway, you can check them out
here, or go to the "will be more updated blog site"
here. (DeviantArt has more up now... But that'll change once the Wordpress site has caught up. Basically dA has all the backlog currently...)
I love this little Quote emoticon, and so I shall adorn my post with his likeness.