Personal Technology -- Personal Technology -- Software to Help You Download From iPods, Share iTunes on 1 PC: "Apple is aware of these shortcomings, and I wouldn't be surprised to see it solve the second one, multiple libraries, this year. But the first, the inability to use the iPod to copy music to multiple computers, is tougher. Apple was forced to cripple the iPod in this manner at the insistence of the record labels, which feared that it might be used to copy music too widely. So a fix probably requires negotiations with the labels, whose obsession with piracy has caused them to treat their own customers like criminals.
Luckily, there are solutions to both problems available today, through third-party software or workarounds. Here's a guide to those solutions."