A year or two ago I was introduced to the community of twistypuzzles.com. 3D printing was just becoming affordable for consumers and I was amazed by what puzzles some people made using this technology.
I wanted to make my own puzzles. With a little help from the twistypuzzles.com community I first self-taught myself how to use AutoCAD, and then moved on to SolidWorks.
It was difficult to get things going but I now run a shop on Shapeways: http://www.shapeways.com/shops/puzzles in which I sell some of my creations. Alas, they're still quite expensive due to the cost of commercial 3D printing.
As a spin off from this, I was also introduced to the fabbing community. I attended a RepRap "masterclass" at ProtoSpace (but did not make my own machine) and as a result I'm now the guy who fixes stuff around the house.
I'm still exploring what else (apart from puzzles) I can do with SolidWorks. To be honest, I'm just creating this profile to take part in the Makerbot giveaway. I would love to have one but I don't want to afford it. Ok, call me crazy for printing $300 puzzles but I actually earn money from that (though the shop). And given that I'm going to university next year, I don't think I can justify spending $750 on something like the makerbot. But it seems like it would be great fun to play around with over the summer.
Too bad somebody already entered a Rubik's Cube into the contest. But I've got some other ideas.