The Answer Is:

• §508 or §504 of the Rehabilitative Act Apply if:

• Are you a government or quasi-government entity?

• Are you an educational facility?

• Do you receive any public funds?

• Do you wish to sell a product or service to a governmental agency or educational facility?

• If the answer to any of the above is "yes" then your site needs to be accessible.
  (see http://section508.gov/ for more info)