3D printing - prototyping on the cheap

Lazy Leg Clamp, originally uploaded by photogeek21.

I had an idea for a modification to my lightstands to make them have the same adjustability as some of the more expensive models. All I needed was a simple split collar clamp with a mount for the struts of the stand.
In years past I had access to the machine shop at work and could have whipped something like this up in a couple hours but now I'd have to look at paying a machine shop $60-70/hr to make it for me - I might as well just buy new lightstands.
I found a on-line service that takes your solid model and uses a 3d printer to turn it into a real world object. They are typically some sort of thermal plastic which would be fine in my case. So using Google's sketchup, I created the solid model of my idea and sent it off - 10 days later I got my part in the mail, tested it out, and by golly it worked the first time - you'd think I was some kind of engineer or something...
I didn't gage the part to see how accurate it was but my slip fit diameters were good. I thought the whole process was pretty cool and I think you'd be able to make some pretty complicated parts that may not be possible in a machine shop - like a hollow bodied part for example.
Cost is based on volume of the part rather than machine time so depending on the part it could work out to be much cheaper than machining. My part here was $26 which is probably expensive for what it is but I couldn't of had a machine shop make that for me at that price.