Ipod charging without detecting the unit.

Hi,
I have an iPod in frequent use. Sometimes forget to charge it and it makes me feel uneasy, since I travel everyday from home to school back and fourth.
My only resort to kill the boredom of the trips I make is by listening to my iPod. Now, is it possible to charge the iPod without detecting the unit via laptop? Not disabling the USB port of my laptop of course.
