IpodLinux

IpodLinux is a distro of linux that is designed to run on the ipod. It uses a patched version of uClinux and is a sourceforge project.

Overview
IpodLinux is more of an enhancement rather than a replacement for the Apple firmware. A bootloader is used to enable you to select between a kernel image and the apple software. Choosing which one to boot is as simple as holding down the rewind key to boot linux, or doing nothing to boot the apple firmware. Also a large number of users have succesfully got it working, and there isn't anything risky about the installation if you follow the instructions carefully. Once booted the linux kernel starts a small linux app called podzilla that has much of the functionality of the apple software. Currently music playback is limited (mp3 only, ogg coming soon), but you can browse the file system, leech files from other devices (including other ipods), use ip over firewire to telnet into your ipod, and write software for it using the Podzilla Tool Kit (PTK) - a work in progress.

For those of you who want to get involved in development, check out the forums while the rest should read the documentation in order to get started installing it.

Currently, the iPodLinux project only officially supports installation on first, second, and third generation iPods however there are methods of installing onto later generation iPods. To install onto an iPod Nano for instance, you can use a tutorial found at IainLearmonth.com which describes the installation step-by-step.