VVVVVV is a retro styled 2D platformer by Terry Cavanagh, creator of dozens of free games. You play as the fearless leader of a team of dimension exploring scientists who inadvertently crash, and are separated. The game involves exploring the strange world you've found yourself in, and reuniting your friends. VVVVVV explores one simple game mechanic: you cannot jump - instead, you reverse your own gravity at the press of a button. The game focuses on playing with this mechanic in a variety of interesting ways. The game is designed not to artificially gate your progress. In VVVVVV there are no locks, no power-ups, no switches, nothing to stop you progressing except the challenges themselves.
A delightfully clever platformer, but not just for the obvious reasons.
This is a platformer which creates difficulty in a very satifying way by subtly urging you to make you hurry, but designing levels so that they must be completed quickly, but not in a hurry.
If you're too impatient, the game will drive you nuts. If you're well-rested, so you can think quickly without running out of patience, then the feeling of accomplishment is intoxicating.
Perhaps the most important detail is that I like it, despite not being the kind of person who likes twitch games or insanely hard ones.
A bit short, but fun nonetheless.