I use Floolahttp://www.floola.com/modules/wiwimod/
Be very careful with these kind of apps though, you have to make sure you choose the correct iPod version when first starting Floola or you risk corrupting the software on the iPod. Remember iPods are designed to be used solely with Macs. Windows users can still avail of it by installing iTunes. But you can't seriously be expected to have to download and install iTunes on every computer you are on.
Floola and other apps circumvent this by putting it inside the iPod. In which case, wherever you go, you can transfer music files easily by simply opening the iPod and clicking the exe file.