I like to make my wargaming terrain as authenthic as possible. I found the Chinese Visual Sourcebook to be useful when I was working on my 25mm Boxer Rebellion project.
Ancients
Warmaster Ancients Late Roman Counters
The League of Ordinary Gamers offers sets of print-and-play counters for playing Warmaster Ancients without the investment of time and money. Their latest is a set of counters for Late Romans.
Destruction of Pompeii Animation
I loved this video animation of the destruction of Pompeii. What strikes me about it, though, is that there seemingly was ample time to get the heck out of dodge.
Papercraft Nativity Set

Schweitzer Comics offers a very nice paper model Nativity Set. It’s not quite free, but it is “pay a fair price.”
Historical European Martial Arts Documentary
Surprise, surprise. Hollywood has it wrong.
Here’s a documentary showing how historical swordfights really happened.