Windows only: If you love your iPod but aren't crazy about iTunes, CopyTrans Manager is a solid alternative that can add media to and organise media on your iPod, iPhone and Palm Pre.
(Click the image above for a closer look.)
This nifty little app is compatible with all iPod models, iPhones (up to firmware 3.1), and also the Palm Pre. Use it to drag and drop media files to your device directly from your Windows PC. You can move music, videos, books, podcasts, movies—essentially any file your device can play. A couple of clicks is all it takes to remove files from your device that you no longer want to carry around with you.
You can also use CopyTrans Manager to create and edit playlists as well as edit individual track information. If you're into album cover art, the app will even import new artwork to your device. One of CopyTrans Manager's best features: You can store it right on your iPod and use it to play music on any PC without installing any files.
One thing this app lacks is a way to copy music to your computer from your device, but we've got you covered there. Give one of the apps from this roundup of iPod/iPhone-to-desktop transfer tools a try. CopyTrans Manager is a free download, Windows only.