Recently, there's been a lot of discussion over whether the text-to-speech reader in the new Kindle 2 constitutes a violation of copyright. Here's the basic argument: If you purchase an e-book for your Kindle, and use the TTS reader to have the Kindle read it aloud to you, that creates a derivative work without the permission of the author or publisher, (i.e., you're using the work in a manner that neither the author or the publisher intended).
I can see the point here, but I think the argument's largely nonsense, and many other prominent authors agree. Rather than link to them individually, I'm going to send you over to this very well-reasoned and well-written rebuttal by Wil Wheaton, who not only links to the other authors' opinions, but also demonstrates the point by first reading a passage from his new book, and then having it read over a TTS reader on his Mac. Make sure to listen to the whole MP3 -- it's about 10 minutes long, but it's an excellent demonstration, and the passage Wheaton chooses is excellent as well.
He also defends the "Oh, well someday computers will be able to do voice inflections just fine and then we'll really be in trouble it's a slippery slope after all" argument well in his comments section, as does Neil Gaiman in this post over here. Good reading.