"Festival is a general multi-lingual speech synthesis system developed at CSTR. It offers a full text to speech system with various APIs, as well an environment for development and research of speech synthesis techniques. It is written in C++ with a Scheme-based command interpreter for general control."
http://freshmeat.net/projects/festival/
Someone else posted this script ,it allows festival to read the contents of your clipboard.
configure Festival (speach synthesizer) to read the contents of the clipboard. If any body is interested, the shell script is
dcop klipper klipper getClipboardContents > $HOME/festivaltext
festival --tts $HOME/festivaltext
With Festival installed Konqueror can read webpages and anything else it can display.
Depending on your distro it should be in your repository.