Bigasoft iPod Transfer is a nice backup utility for the Mac. It allows you to backup some of the content on your iPod back to your computer. The application should support other iOS devices as well, such as the iPhone, and maybe the iPad. I tested it with an iPod Touch and an iPhone 4 and they both were recognized instantly. When a supported device is connected, you will see a summary. This will include the device type, name, version number and capacity. The space used in audio, video and other files will also be displayed.
On the left, you will see the name of your device, and under it, all the different audio and video playlists on your device. In my case, I saw: Audio, Video, 90's Music, My Top Rated, Top 25 Most played, etc. Clicking on any of those playlists will switch the right-pane into a list of files. From there, you can simply check the files that you want to copy to your hard drive and click on the "Copy to hard drive" button on the top. You can also backup the photos that you have taken with the device if you dig through the "Files" folders and find the DCIM folder.
Bigasoft iPod Transfer can put content on your iPod as well. I used it to copy a few songs to my iPhone, and I didn't need to sync the device with iTunes to do it, which is great.