Q.U.B.E.
QUBE's first-person platform-puzzling and sterile white chambers beg comparison to Portal, but the game as a whole falls well short of Valve's franchise. QUBE is shorter than the first Portal, has (a few) more glitches, and is completely lacking in narrative or other story elements. But it does include some cool puzzles, and has a classy presentation. If you actually like puzzles, there is definitely something of value in here.
For its brevity and simplicity, QUBE's full price of $15 doesn't really seem correct. Fortunately the Steam Summer Sale price is a lot more palatable.
Better than: Ilomilo
Not as good as: Portal
Seriously, the similarities to Portal: are impossible to ignore.
Progress: Complete