The New York Public Library’s digital holdings have an amazing collection of color plates of British uniforms from 1066 – 1900. These are great painting guides.
The Jackson Gamers have a very detailed guide to gaming the Russian Civil War.
In N scale here are some free paper models of the tracks of Chicago’s famous “L”.
Terragenesis has a nice article on casting bunkers in plaster from chocolate boxes.
“Pulp” adventure is one of the biggest current themes in miniature wargaming. Here’s a site with a selection of classic pulp stories for you to read online.