At my Mix08 session last week, I showed off a FlickrViewr app that I had written. You can search different user’s photos (or search all public photos by leaving the username blank).
updated: This app has been updated for Beta2. All of its controls now use VSM!
updated: This app now uses DevDave’s AnimatingWrapPanel.
In order to run it on your own, you need to go to flickr and get your own flickr api key.
Special thanks to Pete Blois. I expanded upon his Xml Serialization Flickr library. 
This FlickrViewr application uses:
- Styles
- Control Templates
- UserControls
- Custom Controls
There are also a few re-usable goodies:
- HorizontalWrapPanel (note: the app no longer uses this wrap panel)
- ContinuousProgress control
- ModalDialog
You can grab these separately here.