Yes you can, you can also do just about anything you like ...
Nobody can stop you unless we chain you to a toilet, medicate you til you drool, or toss you in an asylum.
And we are really to lazy to try that.
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Sort of pointless, considering the music you like might not be worth much to somebody else.
Heck, the Pauly Shore Christmas Album and the Drew Carey Show Musical Compendium may even devalue the iPod. 😉