Osprey is offering its basic rules for the popular Frostgrave miniatures game for free.
fantasy
Battle of the Five Armies Scenario
Merlin Larson has a well researched scenario for wargaming the Battle of the Five Armies from The Hobbit.
Gaming The Battle of Helms Deep
Doug Larsen has a nice article and scenario for fighting the battle of Helm’s Deep. He has obviously spent a lot of time studying the source material for both the maps and the forces.
Netherhells Heroic Fantasy Rules
Heresy Miniatures offers a heroic fantasy game called “Netherhells.” It’s a dungeon-crawl game, with players facing a game master.
A Spot of Friendly Wizardry Rules
A Spot of Friendly Wizardry is a set of free wargames rules for battles between two or more wizards.