I know that this is quite off-topic, though mail programs have been discussed here before; nevertheless I do hope that

(a) it is both quite relevant to recent discussions on software development business models
(b) it will be of interest at least to the people here who have used Pegasus Mail in the past (judging by the retro programs discussed in this forum, I trust there are many)

Check it out here: http://www.pmail.com/

Alexander