Sandro talked about his terrific implementation for making one of the first (I'm sure, but can't proof it ..) fully accessible Flash games out there. It got the highest rating by Access for all and they blogged about it.
Unfortunately Sandro can't make his presentation available (his slides engine doesn't have an export function (yet)), but it was basically what he wrote in his 2 blog posts here on this blog. So read Post 1 and Post 2 to get all the information you need.
By the way, the game can be found at postfinance-eventmanager.ch