I got a question is there a way to control and Ipod as a triggerable music player??? It seems almost everyone has the one of these around the house and they are becomming cheaper by the day, so why not try to use one for prop control?
Here are some of the links I have been exploring....
Wired Ipod Remote - I think these can be found for around $10
http://www.usbfever.com/index_eproduct_view.php?products_id=549
Ipod Remote Dissected with contol codes
http://www.maushammer.com/systems/ipod-remote/ipod-remote.html
I beleive it's just a serial protocol ( I looked into it once before ) -- the tricky bit is making the connection. It could be done with the Prop-SX but this is clearly not a beginner's project.
Your main issue is that to get real access to the iPod info, you'll want to become an Apple developer, which isn't free. And then you'll have to buy the special iPod connector to be able to plug into the device. Plus, the iPods change every year and elements of the protocol can change, too...which means updating the code and keeping your Apple developer's status current so you have access to the current info.
It's really too much trouble when you can buy a module that allows you to control music from a USB thumbdrive.