No way, doesn’t seem possible with how Apple has been lately when dealing with their hardware and software and the current attitude towards suing people for touching the insides of their hardware.
But a posting on Boing Boing discusses this.
From BoingBoing:
Open firmware for MP3 players - iPods, Archos, and iRiver RockBox is a set of “open firmware” for various MP3 players, including the iPod, Archos and iRiver players.
Do check it out - looks quite interesting.
Direct link is http://www.rockbox.org/