I was only reading in The Australian yesterday about websites ("Mash-ups") that combine services from a number of other websites.
I found a reference to Mailinator on The Register today. It's a page that maps incoming spam against the source IP address and uses Google Maps to generate a geographical map of where the spam is coming from. Makes you wonder how else you could make use of this kind of info.
Microsoft have made a number of their e-learning courses for Visual Studio 2005 available for free until November 8th.Microsoft Visual Studio 2005 E-Learning.
Sadly, the pages don't work very well with FireFox, so you'll need to use IE to get to the content.
I use Firefox as my web browser, and one of the extensions I always install is the Web Developer extension.
Internet Explorer users look like they are now going to get something similar: IEBlog : Developer Toolbar for IE announced at PDC