LetMeType is an open source application that suggests words and phrases as-you-type. The clever little application builds an index of words that you type and pops up with auto-complete suggestions of words as you are typing. LetMeType is built into the OS and so it works in all applications. Like PureText, a plain text copy tool, this is a small little app and it doesn’t take much time to get used to, but can give you great productivity boost.