John Harper (of fame) has written three short pdfs that are self-contained role-playing games. You can check out Mustang, Lady Blackbird and Ghost/Echo .
What I like about these games is that they seem to represent the same attitude towards design that we see on 1km1kt:
* They're short. Two are two pages long (with artwork) and John has set himself a limit that Lady Blackbird will not go over 12 pages.
* They build on design that has come before. Lady Blackbird has scavenged elements from lots of different indie games.
* They have indie design sensibilities. In Mustang, the course of play is entirely mapped out. The role-playing fills the gaps between the rules. Ghost/Echo is a game you have to figure out for yourself.
* They're open. Others can build on them and make their own free games.
* They are beautiful. Even though John is giving something away for free, they're polished, pretty and really set the mood of the game. I'm often pleasantly surprised by how nice people make a free product - even one done in 24 hours.
What would you say are the 1km1kt attitudes to design? What free gems have you stumbled across?