I usually use my ipod when i'm out skating, cycling or running, and one problem I've been experiencing, is changing songs while in movement. So what I've done is I jailbroke (jailbreaked?) it, and downloaded a program called "Activator" from Cydia. What this has done is allowing me to change songs just by holding down the "volume up/down" button, wich can be done without having to take the ipod up of the pocket.
I'll show you how it's done.
Firstly, install Activator and go into your options, it should be in there with your other programs.
Go into activator->anywhere
If you want it to be the volume up and down buttons like me, chose the "up short hold" and "down short hold"
but you can set it to different buttons if you want. Ex. you can set double pressing the home button to change song, or unlock the ipod, or go into an app.
When you have choosen wich buttons you want, you need to assign them to "previous track" and "next track"
And you are done! Now you can change songs just by holding down the volume up or down button. Wich (as i previously said) can be done without even having to stick your hand down your pocket.
Now there is only one kind of annoying thing about this, and it is that you can't turn the volume down by holding it, but you can still change the volume by pressing the up and down, just don't hold it.
Hope you find this usefull!