Neolithic is a set of free wargames rules for battles with cave men.
A Year of Frugal Gaming Blog has a photo tutorial on making a ruined wall from plywood and other bits.
Dyson Logos offers the Adventures in the New Kingdoms RPG:
Adventures in the New Kingdoms is the setting I’ve been running Fantasy RPGs in for most of my life. It has seen incarnations as a setting for Moldvay B/X D&D, BECMI, AD&D1e and AD&D3.x with side trips into RoleMaster and an abortive attempt to convert it all to GURPS 2e.
The setting itself owes a lot to my first exposure to fantasy novels – the works of Michael Moorcock (specifically the Elric saga). The elves of the New Kingdoms are a doomed and ancient race, warriors and sorcerers of Law who even created their own slave races towards the end of their empire.
The ancient empire of the Kale has collapsed under its own weight and is being replaced by the age of man. Of the three greatest Kale cities, only one still remains within their grasp, the other two being the centres of great human city-states.
Naumachiae is a set of rules for ancients naval warfare for 1/12000 miniatures.
Dungeonslayers is a very well done, old school RPG. The author writes:
Welcome to Dungeonslayers, the role-playing game, in which your characters are slaying monsters and looting dungeons in a primitive and old-fashioned way. The rules of Dungeonslayers were designed to be very basic and simple on purpose, to bring the charm of old-school gaming back to life. Dungeonslayers is not about having elaborate, realistic rule mechanics nor about playing out pseudointellectual dramas filled with egomaniac monologues. Instead it’s about straightforward plots in your traditional fantasy world, where evil is still evil, where monsters are killed mercilessly, where devious traps strike and where fantastic loot awaits, while pencil and graph paper work their own special magic around the gaming table. So, let’s put on the chainmail once again, draw your blade or dig up your spell book, the next dungeon and its monstrous hordes await your return.
The site also has some neat one-page dungeons.