The DigiPen Institute of Technology is known for producing great games and game mechanics, including central elements from Portal and its sequel. The latest project from a group of its students is Perspective, a combination of 3D first-person puzzle game and 2D third-person platformer. The trailer below goes a long ways towards demonstrating how it works, but the central conceit is that you'll need to move through a 3D environment that you can lock into place by clicking, the colored lights in each level creating platforms and barriers for a separate 2D character to move across.
The combination of 2D and 3D perspectives is reminiscent of Xbox indie game Fez, but the aesthetic is very different, with a bright blue and orange sci-fi design and free 3D motion. Beyond the obvious mechanic of shifting position to make platforms appear close enough to jump or walk between, Perspective also takes advantage of things like the platforming character's shifting size and location as you walk through the 3D world, making for some clever puzzles. The game is free to download from the developers' site, for Windows users only.