I asked the same question to myself and had to click around to find the shop and the price. So, you are rather normal!
Thanks not to bad really thought it would be lots more, if your on track a lot this would be a good buy, for me on the commute now couldn't see a real use apart from being flash
I'm surprised there isn't an android/iphone application that does the same thing. I'm sure it wouldn't be that hard for someone who wears glasses. I'd love to have something like this even for the road. Angle of dangle? Cool!