There's an app called DroidShuffle which allows you to control your music playback from your wired headset. You can custom set singe click, double click, triple click, and long click to either pause, skip to the next track, go to the previous track, switch to shuffle, or seek ahead a bit. Also, when using your wired headset in a call, this app allows you to end the call with a long click. I haven't seen any mention of this free app and thought a lot people would like to know.