Instead of lugging a laptop on your next trip, save your aching back by taking your computer's desktop with you on a thumb drive or iPod. Portable Windows software offerings such as MojoPac and U3 put a full desktop on your USB thumb drive (or disk-use-enabled iPod), letting you run applications like Microsoft Outlook and save documents all on that drive. All you need is a host computer: You can plug the MojoPac drive into your in-laws' PC or a coffee-shop workstation, for instance, to access your documents and applications without leaving a trace behind. Alternatively, you can save and run free portable applications--like the Firefox browser, Pidgin IM client, and Sumatra PDF reader--from your thumb drive. Download those and other programs for free at PortableApps.com.