Teammates Amir & Manuel did a cool Channel 9 video showing off Sparkle by building a Flickr photo browser, here.

Amir was able to come up with some excellent stuff, the app is quite slick (and I believe he's made the code available, I'll find a link to it).

On the Sparkle team we regularly have 'App Bash' days where everyone uses Sparkle to create their own applications. It's a ton of fun, and probably the only day you'll see devs in the office before 9AM- submissions have to be handed in by midnight and competition is fierce. A Flickr browser was my first App Bash project, so I'm thrilled to see Amir resurrect the core code. He's done a much better job on the UI than I could ever imagine.

One point I'd like to clarify from the video is Amir's mention of custom controls provided by developers. I worked on a handful of those controls and an extremely important part of each of them is that the control must be customizable and not contain any UI. No pre-canned parts allowed here.

[Update]: (I'm watching the video right now)- that crash that they blamed on me? My code is solid. I swear. I have never written a line of code that didn't function absolutely flawlessly. Ever. Now back to debugging how those code gnomes managed to break my code last night.