One of the IGF 2012 entries to catch people's eyes is Parallax, a brain-hurting pan-dimensional first-person puzzle game from indies Toasty Games. You can see the IGF submission video below.
Built using Unity, the idea is to reach each level's goal by crossing through two overlapping dimensions through various rifts. And it seems to be even more complex in action - take a look:
There's no word on when the game will be finished, but expect to hear more about it as GDC approaches - this looks like one that could capture some judges' attention. (Via DIY Gamer.)