Don't know about the US, but in the UK, we have legislation that requires all websites to be accessible. That means colour blindness friendly too and it's helping drive a refreshment of most of the uk's websites. Good for business.
If you want to make some money, set up a Web Accessibility consultancy.
Here's a good link about the effects on a site for a colour blind person:
http://www.iwss.ilstu.edu/tips/colorblind.shtml
And the good old Visibone site. Great reference for all things colour.
http://www.visibone.com/
A downloadable pop-up:
http://www.visibone.com/popups/
Compared to a colour blind recognition chart:
