While not an absolutely perfect solution - it works only on Windows OS-based systems, operates best in Internet Explorer, and appears to have a problem with representing apostrophes (see screenshot) - CuePrompter allows you to enter up to 2,000 characters into their site, and then launch it as an on-screen teleprompter. You can control [...] Read More...

Read the complete post at http://mashable.com/2008/01/20/cueprompter-web-based-teleprompter-for-videocasters/