Managed DirectX - Have you used it?

So I asked before what types of features you would like to see in Managed DirectX (and the feedback was awesome - I'm still interested in this topic)..  What I'm also interested in that I didn't ask about back then though was what types of things people are using it for currently? 

Are you using it to write some tools?  Game engines?  Playing around on the weekends?  What experiences have you had working with the API?