Classic-Castle.com

I've been doing some quick research on Vikings for a display, and had to wade through quite a few sites in order to find a few good ones. I thought I'd link the more useful ones here, in hopes they'll be interesting or useful to someone else.

http://www.hurstwic.org/history/text/history.htm
http://www.cdli.ca/CITE/vikings.htm
http://www.foteviken.se/engelsk/indexe.htm

I'm no expert on Vikings, so I can't vouch for the accuracy of these sites, but they at least seem like a good start.