Make a better screen reader

@partiallyblind told us screen readers are all rubbish. Let's make a better one

Me Submitted by Carrie Bishop
FutureGov Team Hack
What could FutureGov fix in a week?

I have no idea how achieveable this is, but during Joshua Marshall's great talk he mentioned that most screen readers are very old, badly designed, and cost up to £900. Could we make a better one that is open source and free (or cheap) for people with disabilities to get the most out of the web?