I recently started playing around with Silverlight in SharePoint. I took a look at the Silverlight BluePrints to start with... Oh man, what a hell to get a sample working! A lot of people were complaining about a blank webpart... and of course I had the same problem. Recompiling the Silverlight project in VS 2008 helped for me.
After trying a few examples from the BluePrints I took a look at Visifire...
Visifire is a set of open source data visualization components - powered by Microsoft® Silverlight™. With Visifire you can create and embed visually stunning animated Silverlight Charts within minutes.
I examined the Asp.net example and gave it a try to build a chart based on some list data.

A sample SharePoint list with some data (Year and Profit)

Based on the data from the SharePoint list I created a Silverlight Column Chart. Looking good isn't?

You can also choose other visually stunning animated charts.
eg. line charts, donuts, columns, ...
To bring this to a next level... I'm trying to embed this in a SharePoint webpart. I was thinking about the SilverLightPart "wrapper" webpart from the BluePrints to do this job. Normally, this webpart is able to wrap a .XAP file to embed your silverlight applications. But first, I'll have to create a new Silverlight application to create a .XAP file (The above example is just an aspx page) . I am working on this...
It all looks well, but still in its infancy! :)