I have no idea if this is possible within the constraints of the Android API, but I figure it's worth asking.... One of the (few) things I miss from my Blackberry Storm is the ability to change tracks by long-pressing the volume buttons. I considered that function absolutely invaluable on a touchscreen device, especially since I keep my phone holstered (face-in) on my hip. My implementation of choice would be to hook the Volume-Up, Volume-Down, and Camera buttons when the screen is locked. Long-pressing Camera would toggle Play/Pause. Holding down Volume Up/Down would trigger Next/Previous after about 3/4 of a second. A short press of Volume Up or Down would change the volume by one notch on button-release. The lack of this feature is the sole reason I still sometimes pull out my Storm to listen to music, when I know I'll be in a situation that would make touch-controls inconvenient.