By now, most people who buy music from the iTunes Store know that one of the ways to legally get around the DRM restrictions on your purchased music is to burn a CD of that music and then rip that CD back into iTunes as unrestricted MP3 files. While it's true that there's some quality loss associated with that process, it's satisfactory for many people. The process is still a pain, though, particularly if you have a full library of purchased music that you want to un-DRM.
DRM Dumpster, from BurningThumb, isn't magic and it doesn't perform any new tricks. All it does is automate the task of burning a CD-RW and then importing your music back to iTunes. It processes your entire iTunes library, not selections, so there's no need for it if you only have a few songs or less than one CD's worth of music to convert. By using a CD-RW, DRM Dumpster is able to erase and reuse a single disc to handle your entire library without you having to babysit and pop discs in and out of your optical drive.
DRM Dumpster is "donationware" and requires Mac OS X 10.2 or later, a CD-RW disc and a CD-RW-capable burner. It's been tested with iTunes 7.