I Really carry a bad attitude.
I respectfully submit that *ever* depending on intimidation factor, ESPECIALLY WITH A KNIFE, is a potentially fatal mistake. I have carried a knife on my person almost 100% of the time for years, but even if I had no other options (firearms, improvised weapon, etc), I would NEVER attempt to "scare off" a potential attacker with a knife. If you have to use it, the BG shouldn't know you have it.
Anyway, that said, I once carried my Glock 23 most often, when not at work (little guy, casual environment, in the South), where I carried my P-32. When I was kicking around in the boonies for a few months between Service and school, I was usually packing a 3" Model 657.
Now, I mostly have a P-3AT or Seecamp .25.
John
edit- I see Navy Joe has a fantasy carry category. I'll play. I once carried a Colt Anaconda 8" .44 concealed in a shoulder rig. Once. For my fantasy carry, I think I'll take a Para-Ordnance double-stack rig in 9x23mm, IWB.