Mekton Alpha - A Free Introduction to Mekton Zeta
From the introduction:
Mekton Alpha is a free introductory set of rules to the popular Mekton Zeta Role-Playing Game.
These rules will give you a taste of the actual game, but just a taste. One can run a fun mini-RPG session with nothing but these rules, but the full Mekton Zeta rules provide 1000 times more detail, more explanation, and more fun.