Accessability and the impaired.

I, as most of us probably do, know quite a few people who are physically impaired in some way. I never gave it much thought, but without web accessability these people are missing out on the information super-highway. I know that the amount that each of these people use the internet varies from not at all, to quite a bit. The interesting thing is, I was talking with a blind guy about English. He said that he reads a lot of web pages and didn't understand a lot of the punctuation on these. I never really thougth before about blind people using the internet. I wonder how many web pages are out there that really support these devices.