Matchbox is an Open Source base environment for the X Window System running
on non-desktop embedded platforms such as handhelds, set-top boxes, kiosks,
and anything else for which screen space, input mechanisms or system
resources are limited.

Matchbox consists of a number of interchangeable and optional applications
that can be tailored to a specific non desktop platform to enhance usability
in a 'constrained' environment.

The core and most developed application is a window manager with a classic
stack based PDA like management policy.  It supports modern window management
standards, cutting edge X capabilities, advanced themeing, and various window
types.

WWW: http://matchbox-project.org/