Rockbox developers have come up with a new firmware for most ipods. Rockbox replaces your current ipod firmware, and most evryone considers it to be better. It improves upon the sound - greatly increases sound quality, especially with the included custom EQ. It supports lossles, high quality audio, such as flac, something any audiophile would want. Perhaps the biggest benefit comes to the average user, who can now customize those boring white and blue ipod screens, and add completely new themes and background pictures, truly an amazing feature.
Rockbox is compatible with the following ipods: 5G (Video), 4G (Color/Photo/Grayscale), 3G, Nano 1G, Mini 1G/2G. It is also compatible with the iaudio X5, as well as many Archos mp3 players.
Here's their site: www.rockbox.org.