Chromatron 1, 2, 3 and 4 just became freeware. In these little standalone puzzle games for PC and Mac, you align splitters, benders, and mirrors to direct colored laserbeams into like-colored targets. Enjoyably difficult, and an example of great game design. [more inside]
SHOOT THINGS - a retro-arcade-style shooter for Mac OS X. The author's page describes how it was written in 3 weeks for a contest - it's entertained me for considerably longer than that.
Get Hostile! - Inspired by the well-beloved Avalon Hill board game Acquire, Get Hostile! is a free, web-based board game that has already sucked up hours of my time. Check out the quick tutorial to get up to speed, then play against live opponents or AI's, forming corporations, buying stock, and doing hostile takeovers!