In design, this looks like a Sonic level... minus the coins of course. This is really nice looking and the shading technique kind of reminds me of Yoshi's Island for the SNES. Ah, memories.
Want to give some dough back to all those amazing pixel artists? Donations provide prize money for contests, help cover hosting costs and support new initiatives.
Maybe it's the sky gradient and stone textures, but this reminds me of a game you might see on an Amiga.