A computer science student named Erik Roystan Ross has recreated the first level of Super Mario 64 in high def and made it available to play online. I haven't tried it myself yet (I think I have to install something?) but I've watched the YouTube video, and it looks crisp.
It's funny how, more than anything, it's the sounds and music that bring me back. I'm a huge fan of the SNES, always will be, but I remember standing in a Target store and watching that first Mario 64 demo and being blown away by it. The music is so... peppy, and the sounds so cartoony. I think I may have to pull my N64 out of the closet this week (or at least my DS copy of the game).
According to PC World, the level isn't a perfect copy, but to me it still looks like a great revisit. Makes me wish Nintendo would return to the title and do a polished version for the WiiU with all new textures and the like. I'm sure I'd still be terrible at it; I should probably just stick to Super Mario 3D Land.