Micro Drive

A one-inch hard drive in a CompactFlash?-compatible form factor and interface. The name is currently [May 2010] trademarked by Hitachi, though other manufacturers produce comparable drives.

http://en.wikipedia.org/wiki/Microdrive

CobWebs from 2001:

http://www.storage.ibm.com/hardsoft/diskdrdl/micro/index.htm See also: http://www.nvg.ntnu.no/sinclair/microdri.htm :-)