In a historical sense, the best handgun is probably a 1911 or Colt Peacemaker.
But for me, it's my CZ 75b. I have guns that carry higher price tags and are supposed to be "cooler". I've got a Glock, XDm, Sig 226, BHP, 1911, etc...but a CZ 75b that I paid $409 for (new, OTD) probably makes me look like a better shooter than any of them. Great quality, quite a bargain, and an outstanding gun. I highly recommend this gun time and again.
"The Future is Unwritten"