Soothsayer is an intelligent predictive text entry platform. Soothsayer
exploits redundant information embedded in natural languages to generate
predictions. Soothsayer's modular and pluggable architecture allows its
language model to be extended and customized to utilize statistical,
syntactic, and semantic information sources.

A predictive text entry system attempts to improve ease and speed of
textual input. Word prediction consists in computing which word tokens
or word completions are most likely to be entered next. The system
analyses the text already entered and combines the information thus
extracted with other information sources to calculate a set of most
probable tokens.

WWW: http://presage.sourceforge.net/