Crush The Fascist Vipers is a set of free wargames rules for 6mm WWII games.
The Miniature Wargaming Editor
Police Action 6mm Vietnam Rules
Police Action is a set of free wargames rules for 6mm Vietnam games.
De Bellis Horribilis WWI Rules
De Bellis Horribilis is a set of free wargames rules for The Great War based on DBA.
Furious Reason Rules 18th Century Rules
Furious Reason is a set of free wargames rules that combines Fire and Fury with Age of Reason.
Building A Medieval Roadhouse
Terrain Thralls has an illustrated tutorial on making a half-timbered, two story roadhouse. The end result is beautiful, and would be useful in a wide variety of settings.