Snowie www.oasya.com The one and only.
Jelly www.jellyfish-backgammon.com First and not least, Jellyfish neural net backgammon is still a great buy.
GNU (http://www.gnu.org/software/gnubg/gnubg.html) The “gnu” kid on the block. It isn’t the most user friendly, but some claim it’s the best.
Sconyers’ Database (http://www.bkgm.com/rgb/rgb.cgi?view+1043) The last word in bearoff software.
Walter Trice www.flintbg.com Walter has developed various pieces of useful software, the best being the MEG (Match Equity Generator).