Tiny & Big: Grandpa’s Leftover is a physics based third person platformer with a sandbox attitude. The game offers 3 gadgets: A ray cutter for slicing the whole environment like butter, a grappling hook for pulling stuff around and rockets to send the pieces into the sky.
For actual gameplay footage check out this 19 min video by TotalBisquit.
Sugar Cube: Bittersweet Factory is a single screen platformer with a background tile flipping mechanic. The sugar cube that you control can turn background tiles into platforms, elastic springs, spikes etc. by simply touching them. This ability allows him to reach the exit door in each stage. Interesting concept.
Out There Somewhere is an adventurous platformer with a teleportation mechanic. It works like this: When the laser beam of your gun hits a wall you will be beamed to that exact position. You can also use the character’s momentum by jumping quickly before the laser hits a wall. (That way you reach higher places after the teleportation)
Note that the beginning might be a bit slow and too easy but after ~10 minutes the puzzles get really good (as soon as you have collected a proper gun to kill enemies).
Also consider to read this Review on RGCD