Misu is what you need if you're tired of having to open up iTunes to exchange music between two iPods.
The nifty little program allows two iPods to connect to each other and merges their music collections.
Any song that you don't have from the other iPod will be added to yours. The program is also very easy to use. Connect both iPods via the USB entries in your Mac, launch Misu, press 'Transfer', and let it take care of the rest.
The process can take a little while if your exchanging a large number of tracks.
Obviously it would have been nice to be able to browse through the other iPod's library and select only the songs you wish to transfer, but it's still not a bad thing being able to exchange music in one go.
The application is also fairly stable and requires little knowledge to run.
Misu is the perfect program to exchange music between two iPods.