The term Ultra-Mobile PC (abbreviated UMPC), or Project Origami, is a specification for a small form factor tablet PC. Project Origami Ultra-Mobile PCs have a 20 cm (8-inch) or smaller touch sensitive screen at a minimum resolution of 800 × 480.
UMPCs have enough processing power to support audio, video, and gaming, in addition to having rich support for browsing the internet as well as for other communication and networking applications.
UMPCPortal - The Ultra Mobile Computing reference site
UMPCPortal started as Carrypad.com a blog started in Feb 2006, itself the result of a personal quest to find a device that would complement a ‘three device strategy’ – The mobile phone, a desktop PC and the missing component – a ‘Carrypad’.