I can’t read German, so I don’t really know what it’s about, but this page has some excellent antique plates of European uniforms from the late 1700s and early 1800s. (The dates actually range from 1697 to 1867). It’s worth a look if your doing wars of that period. There are quite a few Napoleonic period plates in here.
Uniforms
Birds In Uniform
Fans of uniforms might find these illustrations of birds in uniform amusing.
Soldiers of the Queen British Military Photograph Site
The Soldiers of the Queen site is a great resource for anyone who games with Victorian Era miniature soldiers. The site is stuffed full of photographs from the era. A must see.
Evolution of Napoleonic Uniforms
The Evolution of Napoleonic Uniforms website is an ambitious work. It is not by any means complete (could any project of this scope ever be complete, given the number of variations?), but is worth browsing through.
Indian Army Uniforms of the 1930s and 1940s
The Princely States Report website has some neat color plates of Indian Army unforms from the 1930s and 1940s. They’re originally from a pack of 50 Players Cigarette Cards.