The open source community Codeplex has got a portable and light weight application that reads out text. So it is basically a very useful and light weight application that can be used to read text aloud through a robotic voice. Its called Clipspeak. Some interesting features are:

1. Record the audio to MP3 (turn text to MP3 OR ebooks to audio books)

2. Copy paste text to be spoken. Stop ongoing speech.

3. Change voice parameters.

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