I was poking around for good Christmas games (so far Sufjan Stevens' game is the only one worth mentioning) and I found Sky Island. Quite honestly, it looks like a prototype or clone of Fez (that one game from Indie Game: The Movie that still hasn't come out yet). Basically, you can only move in 2D space, but you can rotate this space. It is kind of mind-blowingly difficult for me. I think the concept of moving your camera and changing the landscape is cool, but so far I haven't been impressed with the game's teaching me how to navigate space.
I admit, most of the time if I get frustrated with a game I usually put it down. I like the idea of games gradually getting more difficult and teaching me to get better, though I concede that the whole Dark Souls difficulty discussion makes me wish I cared enough to persist through abusive games (oh, excuse me... games with a "Darwinian learning curve"). I think players need to feel some sort of attachment to a game before it throws something really difficult out there, which probably explains the whole boss-battle cycle. Anyway, some games are hard and I just give up.