The device was announced at Macworld last January, and is currently the only really practical way to use Mac OS X Leopard's backup program Time Machine without physically plugging a hard disk into the computer.
A wireless backup option for Time Machine had in fact been an advertised feature leading up to the OS X Leopard release. But all references to the option were mysteriously pulled from Apple's product literature last October.
Time Capsule is essentially composed of an Apple Airport Extreme Basestation Wi-Fi router with a "server grade" hard drive attached. The box has dual-band 802.11n antennas for 2.4GHz or 5GHz frequencies, three Gigabit LAN ports, one Gigabit Ethernet WAN port, and a USB 2.0 port.
The device retails for $300 for a 500GB drive and $499 for a 1TB drive.
By our extremely rough calculations — that's a $43 markup compared to an Airport Extreme, a 1TB drive, and a roll of duct tape. But perhaps we're missing the point.
