These are games that have been made for game jams, which are game-making competitions with tight restrictions on time.
A few of these games weren’t finished in time for their respective competitions. Many of them have been improved afterwards, which is usually signified by a version labelled “post-jam” or “post-compo.”
Ludum Dare #27: Ten Seconds – Pro Crastinator
Features good graphics that were made entirely in-house, but sound is conspicuously absent.
Ludum Dare #26: Minimalism – Minimal Adventure
Intuitive, minimal controls and nice sound. However, the awesome intro that was added Post-Compo belies the amount of gameplay that’s actually there.