Isn't there, like, Eudora and some Oracle stuff, and several other corporate content management blobs that do complex email management, too?

Pegasus Mail (http://www.pmail.com) is still going strong, slowly trudging towards the 5.0 release. Though there were a few hiccups related to the financial viability a couple of years ago, development is still going on and the product is still free.

Lotus Notes. It will never die.