This looks like a neat idea – a pen which records both what it writes and what it hears. It’s aimed at people taking lecture notes, but would likely be just as suitable for any other annotated-audio situation such as meeting minutes or the record and replay of spoken games.
Of particular interest is the bit where it notes:
Livescribe plans to maintain a clearinghouse online where users can download new applications, some created by the company and others by users. (Anyone who can program in Java can write software for the pen.)