Frag Zombies is a set of rules for combining Steve Jackson’s Frag game with Journeyman Press’ Zombies! board game. Of course, ownership of both sets is required, so I’m not sure how useful it will be.
The Miniature Wargaming Editor
Dawn of the Dead board game
O.K. So it’s not miniatures, but anyone my age will remember the classic SPI game “Dawn of the Dead.” There’s a downloadable version here.
Red Actions!
The Perfect Captain offers “Red Actions”, another in their series of superb free wargames rules. This particular set is designed for miniature wargames in the Russian Civil War. Like all of the Captain’s rules, these have superb graphics — but they are not just gratituous pictures. The thing that makes these rules so special is how tightly the graphics are integrated into the game system.
Scavenger Skirmish Survive
Scavenge Skirmish Survive is a set of free wargames rules for a tabletop game set in a post-apocalyptic volcanic winter. Link goes directly to a pdf
GURPS Lite
Steve Jackson’s GURPS (Generic Universal Role Playing System) is one of the grand old men of the role playing world. The game provides one of the most realistic, detailed gaming systems ever. Because the combat system is so good, I know of many miniature gamers who use it for skirmish games. Steve Jackson games has released a free “lite” version of the rules as a pdf download.