It's great to see so many Silverlight-based widgets, samples, demos and applications appearing out there. I spent a happy hour this morning searching around the Internet for examples and samples, and thought I'd aggregate the fruits of my research below.
If you've just installed Silverlight on your machine and want to see it "do" something, click around the fifty links below to explore. Some of these samples require the Silverlight 1.1 alpha release (Windows install / Mac install), so if you get an error, try installing the 1.1 release. (Incidentally, the 1.1 alpha release contains the 1.0 beta bits, so you just need to install from the link above and you're good to go.)
I should probably just add the disclaimer that since these are hosted on a variety of external servers, it's almost guaranteed that some of the links will be broken at any given time. Have fun!