How do I change the function of the earphone button? I have a Nexus S running Gingerbread and I use the stock app to listen to music. The bundled earphone has a button that plays/pauses music, but I find this redundant since I can either reduce the volume or pull out the earphone jack when I want to interact with the rest of the world.

It would be really awesome if I could change the function to "Next Track" instead since it'd be easy to skip a track while I'm on my bike. Is there an easy way to achieve this?
I'm guessing you've tried double clicking it? On my phone (Dell Streak), a double-click skips to the next track. Might just be DoubleTwist that, though, I'm not sure.