A great skirmish level wargames table is littered with the paraphernalia of modern life. Here’s a site where you can get free print-and-play models for things like coin-op video games, boxes, pop machines and more.
English Civil War Rules
MAWS offers a set of free wargames rules for the English Civil War. They’re meant for 25mm/28mm figures wehre one figure equals 10 men
Phalanx Ancients Rules
Phalanx is a set of free wargames rules for ancients. Designed for 6mm, 10mm, 15mm, 20mm, HO/OO and 25mm scales, the authors say it emphasizes speed of play while maintaining a good leval of accuracy.
Making Disrupted / Shaken / ETC Counters
The Wargaming Site has a nice method of making custom markers for your games — shaken, distupted, wounded, etc.
Battle: War At Sea Modern Naval Rules
Battle War At Sea is a set of free wargames rules for modern naval warfare. It is designed for 1/6000 scale ships