It's all very exciting.
Oh wait. That's something else. This isn't very exciting. But it is very useful.
I've needed a decent progress HUD in my apps for a while. I was using ATMHud for a while, and while that works, it doesn't take the device rotation into account. Plus, it was a bit messy - you had to register it with your base window.
So I had a look around, and found SVProgressHUD which is referenced by pretty much every iOS app out there. I don't really like using ObjC bindings unless I have to (read: too much code to port), so on a recent long haul flight to Japan, I ported SVProgressHUD to MonoTouch.
And so, I give you BTProgressHUD.
As I said, not overly exciting, but very useful.
More info is on GitHub, including a sample. Feel free to use it, and submit bugs and the like.