This Urban Desk is by UrbanNature, a space-saving furniture brand started by German industrial designer Jörg Brachmann.
It's not a full hideaway desk, but tucks its lower worksurface away in order to become less obtrusive. The mechanism is low-tech and human-powered.
"The fixed superstructure remains in place when the desk is extended. This means the monitor, lamp, and work accessories don't need to be rearranged each time. Two integrated A4-sized drawers provide additional storage for documents and everyday office supplies."
The Urban Desk is made of Ash, and sells in Europe for €995 (USD $1,114).