I would like to see multiple trees accessed via tabs as implemented in TreeDBNotes, Keynote, and MyInfo 3.
TreeDBNotes (freeware and pay versions)
http://www.softviewer.com/treedbnotes/
Keynote (freeware)
http://www.tranglos.com/free/keynote.html
MyInfo 3
http://www.milenix.com/index.php