Wooden, Binary calculator

I bought a binary clock once because I thought it was cool. I got it from Think Geek for about $15, but little did I realise that the tax that I would have to pay would double the price. A friend at work also bought one, and we set his up in the office. First we had to get an American to English plug adaptor, and then we used it... and it started smoking and then stopped working. I didn't use my clock in the end.

Anyway the only reason I thought of this wonderful little story is that I found this funky wooden, binary calculator today.

The calculator is a little wooden machine that lets you add numbers with marbles. Obviously it's kind of redundant what with computers and, well, real calculators, but I think it's rather cool - and would be a good way to teach binary to those who don't know/ understand it. I tried to teach binary to my girlfriend and she called me a geek, then she made me explain until she understood.