PodMaxx
Neat stuff this. Share music iPod to iPod' with NO RESTRICTIONS! Nice. You can hook up you PC to ANY iPod as if it was your own. Host of other features, but just the iPod to iPod' gets it my vote.
iPod Software, iTunes Alternative

PodPlus
This iPod software lets you get your music off your iPod as well as putting your contacts, emails, RSS feeds, podcasts and more on to it.
iPod Software, iTunes Alternative

iWriter
iWriter lets you take full advantage of your iPods notes feature. You can make anything from a simple text game to product brochure for your customers.
iPod Software, iPod Notes

iArt
iArt allows you to download album art and lyrics for your iTunes library which can also be viewed on your iPod
iPod Software, Album Art

Markable
Markable gives you the ability to convert recordings from many audio formats including MP3, WAV and Audio CD into an audiobook format your iPod will understand
iPod Software, Audio Books

Pod Player
With Pod Player you can listen to music on your iPod from any computer you plug it into, without the need for having iTunes installed
iPod Software, iTunes Alternative

MarksMan
MarksMan lets you back up old bookmarks and create new ones for audiobooks stored on your iPod.
iPod Software, Bookmarks

TuneJack
TuneJack provides a very easy to use wizard to easily copy songs from any iPod to your PC and/or iTunes.
iPod Software, iTunes Alternative

iRemote
iRemote is a freeware program that lets you make a skinable interface to iTunes.
iPod Software, iTunes

GoogleGet
GoogleGet is a small program to help you get news and weather from news.google.com in the simplest and fastest way possible.
iPod Software, Google Tool