The Veni Vidi Vici site has some great photos of Dark Ages miniatures. I’m painting a variety of Dark Ages armies and always like to reference other peoples’ painting projects. These are really good.
The Warfare East site has a jpg image of Teutonic Knight banners to download, print and cut out.
Merlin Larson offers a list of battles with Vikings from the Anglo Saxon Chronicles. The most interesting thing he found was that – contrary to the mythology — the Vikings were not necessarily superior in battle to the Anglo Saxons.
For gamers interested in the historical King Arthur, Arthuriana offers an interesting site.