Some discussions I've been part of recently on using text to speech (TTS).
The first link is part of the RSC YH Excellence in Inclusivity event held at Sheffield's The Source: http://ietherpad.com/eii3
I chaired the sessions where we were pulling together people's knowledge of text to speech software. I was also able to show them text to speech apps or software on mobile devices: the google android phone, a windows mobile phone and an iPhone.
Di held an online Instant Presenter session on text to speech for those of us undertaking the ITQ for Accessible IT practice. I found the exercise of looking at various TTS software/websites with headings to push my thinking an excellent way of stretching understanding. Di mentioned the RNIB protocols, using headings. More on this here.
I looked at Fireflox Click speak but it didn't play on my mac. Not sure why - have to explore further. Also looked at Yakitome.com and my comments on this are one this etherpad (http://etherpad.com/itqsession4), but will pull my contribution together for my portfolio.