I've created a table for all the little robots featured on instructables to drive around on. It has the height of a standard coffee table and is constructed from very basic and cheap materials. The table has an elevated edge of 50mm to ensure that the bots don't fall off the surface.
For some examples of robots this table can handle you can check out the following links: Bristle bots: http://www.instructables.com/id/No-Solder-Funny-Robot-in-Minutes/ Drunken drawing robots: http://www.instructables.com/id/Drunken-drawing-robot-/ Vibrobot: http://boingboing.net/videos/vibrobot.mov
To make your own you need the following: materials: - wooden panels (OSB) - small scews - metal corner fasteners
tools: - (electric) screwdriver - table saw (or order the OSB panels with specific dimensions)