Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
http://www.monoprice.com/mobile/pro...categoryid=10910&subcategoryid=1091002&cpncd=

Or...

http://www.monoprice.com/mobile/pro...categoryid=10910&subcategoryid=1091002&cpncd=

I use the wider one. Have 24" monitor on it, and my Mac mini sitting under it. Mini has a USB external DVD drive sitting on top of it, with about 1" of space to spare on top.

It should work fine for a MBP with an external monitor and Bluetooth keyboard and mouse, but sounds like you want something smaller, so maybe the first one would be better for you. You didn't specify what you mean by "small workspace" though, so I've pasted links to both just in case.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.