This software looks interesting: GhostReader from ConvenienceWare. It will translate text on your computer, from public domain novel downloads to email & news site text, and convert to audio speech in a variety of selectable voices. I especially like the suggestion to use the software to convert your own writing to speech for proofreading - or is that prooflistening? It will even read foreign language text. Price seem resonable at $39.95.
Image from http://www.convenienceware.com/