Since 1998 or so, PC users have been living in the USB era. The convenience of USB plug-and-play operation makes every computer user's life easier, and that advantage extends to removable storage as well. Small, portable USB-powered hard drives (lower left) are common today; they hold lots of data and get cheaper every year. Even more popular is today's reigning removable-media champ: the USB thumb drive (introduced in 2000). In coupling flash media's rapidly growing data-storage capability with conveniently small size, the USB key is the format to beat--and it might prove to be the last removable media we'll need.