Morgalad is a fantasy RPG set in a pre-medieval world. You can download the starter set for free.
For GURPS players, here is an online automated treasure generator.
Cybercity Blues is a free RPG that has a lighter take on the cyberpunk genre. The authors write:
“Cyberblues is a bit like Cyberpunk, only more mellow.”
Cyberblues City is a near-future, action-adventure roleplaying game. Fast-playing and often funny, it offers a lighter take on the cyberpunk genre, both in terms of system and tone. Cyberblues City uses a much modified version of the Fudge roleplaying system designed to make it easy on GMs. And best of all, it is absolutely free.
Legends of Time and Space is a free role playing game that takes its inspiration from Steve Jackson Games’ The Fantasy Trip.
Metagaming’s The Fantasy Trip is one of my favorite games of all time. It’s one of the core products that drew me inexorably into the gaming world. Here’s a page with a great number of resources for The Fantasy Trip.