Indie games? I've played the demo for Limbo, super great game. Funny enough, there is another indie game with very similar aspects (panoramic style left-to-right gameplay, puzzle solving) called Deadlight. Deadlight I bought, but I got epically stuck. Before being stuck, it was a fantastic game where you're a father trying to get back to his wife and child in the midst of a zombie apocalypse. The background detail is gorgeous. But the autosave feature doesn't save as frequently as it should and I find myself having to escape a corrupt army holdout over & over & over because the person I am trying to rescue is a tard and can't keep up, thus resetting my progress to 0 everytime. So yeah, I stopped playing that.
Some of these aren't Indie, but I enjoy playing them.
Fez (XBLA): 2D/3D Puzzle Platformer with a nice 8Bit feel.
Journey (PSN): Love this one! It's an adventure/exploration game with beautiful music, characters, and environments. There is a pseudo co-op mechanic, too.
Don't Starve (Browser): It's a silly survival game where you're dropped into a randomly generated map and have to collect items, do crafting, and fight monsters to see how long you can go without starving to death. [link]
ChronoBlade (Browser): This one isn't out yet, but you can sign up to be part of the closed beta testing. It's a 3D Side-Scroller Action RPG that is set in a Multiverse. It's like DFO meets Diablo. I'm the VFX Artist on ChronoBlade and I'm having a lot of fun working on it and playing it. [link]