The World Of Gainar is a massive work — a complete RPG system set in a post-apocalypse fantasy world. This is no Gamma World, however. From my reading, it seems to be more of a traditional fantasy — with dwarves and elves (fey), swords and shields, but also with gunpowder and steam tech. For those who just want the background, there’s a stripped down version that’s just the world book.
Warrior and Wizard is an RPG and Combat game apparently inspired by The Fantasy Trip.
Seven Hex Dragon has some free pdf character sheets for The Fantasy Trip.
JAGS stands for Just Another Game System and is described as a “rules heavy” universal RPG system. It’s gotten some notice around the ‘net and is available for free as a pdf or you can pay to get a print version.
The Basic Fantasy Role Playing game is just that — a role playing game released under the Open Game License. it’s based on the d20 3.5 rules, but takes its inspiration from old school role playing.