Wikipedia
OQO
OQO was a U.S. computer hardware company that was notable for manufacture of handheld computers. Its systems possess the functionality of a tablet PC in a size slightly larger than a personal digital assistant (PDA). According to Guinness World Records, the "OQO" was the smallest full-powered, full-featured personal computer in 2005. The company's first version of subnotebook computer is the OQO model 01. Recently, it has been compared with the Ultra Mobile PC platform, although it was introduced before the UMPC took flight.
OQO was reported to have stopped production in April 2009 because of financial difficulties. The company's web site indicates that OQO ceased operations entirely as of April 2009.