A buddy sent me a link to this video. It is a very neat machine/sculpture where steel balls roll around the structure. It kind of reminds me of Marble Works on steroids.
Steel Circus Kinetic Sculpture
BTW, if anyone finds a better Marble Works link, post it as a comment. I need to run to work and don't have time to look more.
[Update 2 Nov 2006] My mom found a link to a page selling some Marble Works toys: http://www.discoverytoysinc.com/toys3b.htm