One of the most noticeably missing features in the current Silverlight bits is the lack of controls. They are planned for version 1.1, you can see a list here, but in version 1.0 or in the 1.1 alpha you need to roll your own.
And that's exactly what ComponentOne has done a very thorough job of doing. "Sapphire" is the name of their Silverlight Toolset which at this time includes 31 controls ranging from a Button to a DockPanel to a DateTimePicker.
They've also provided a sample application in the form of a functional Amazon store front. The main UI star is the HyperPanel (pictured below) which offers a fish-eye view of the items inside the container.
I've said it before (at least in person), but this is an exciting time watching the world around Silverlight come together and grow. Looking forward to the v1 release!