Free Open Source Thin Client Solution - OpenThinClient

openThinClient OS

The openThinClient OS is an operating system based on Ubuntu Linux which may due to its open architecture integrate hardware of different manufacturers. It covers the whole range of ThinClients' boot architectures.
For security reasons the user hasn't got any access on the operating system. Applications and software updates are maintained and performed centrally on the server by the system administrator.

http://openthinclient.org/openThinClient+OS?bl