Tactical Game X is a modern take on the classic Panzer Leader / Panzer Blitz games, which now are pushing fifty years old. They’re still great, though, and if you love them, you might want to take a look at Tactical Game X.
Cheapass Games offers Renfield, a card game about parts, tools, gravestones and “yummy delicious bugs.”
Years ago, GDW used to hand out copies of a simple Frank Chadwick game called Battle for Moscow. I’ve got a copy, and have used it to introduce players to board style hex wargaming. If you dont’ have a copy of this classic, you can download it here.
The Barons of Fyn is a free downloadable card and tile game from Bones Games. In the game, rival barons try to expand their borders, building a fiefdom of loyal towns and cities, and strengthening their armies. It’s beer and pretzels for 2 to 6 players. I’ve played this, and its fun.
Floating Islands is a free print and play game about building an archipelago from floating sky islands.