One of us—ok it was me—picked up a T-Mobile MDA (HTC Wizard) yesterday and have been messing with it nonstop. It's very timely that our buddy Phillip Torrone from MAKE pointed us to the video he made using the old pPod software that Apple had canned a while back to turn the MDA into a makeshift iPod.
The controls work fairly well using the touch-screen of the MDA and mimics, in our opinion, the best generation of iPod controls.
The software's still floating around, so if you want to try it yourself you can either google "Turn Your Pocket Pc Into An Ipod!" or take a look at one of the links in this post. Guess which one!