Social+Studies+Resource+Sites

I can't remember if there are any other secondary social studies people out there, but I'm hoping to start a section of the wiki to compile good links to sites with social studies resources, lesson plans, or general class ideas. So far the sources I've listed I've found mainly through the November book, so I'd love to have other outside contributions. Please add in anything you may find!

An obvious gold mine of primary resources, as well as lesson plan ideas - The National Archives! [|www.archives.gov]

Discovery Channel's site with geography lessons based around series of short videos about different countries and cities: [|www.discoveryeducation.com]

A site about explorers with pre-made webquests: [|www.allaboutexplorers.com]

An assortment of random but detailed social studies lessons ranging from K-12: [|http://www.csun.edu/~hcedu013/plans.html]