Kel Tec P11. The long, hard trigger pull is a safety factor on this pistol with no manual safeties. When you want to shoot it, it'll shoot, but you have to mean it. I think that's a good thing on a pistol designed for personal defense only. When considering pistols in this size and weight class, you must sort them by type. The Kel Tec and Taurus Millennium have similar operating systems (in effect), but the Taurus also has a thumb safety that flips down to fire, like a 1911. Neither gun has what you would term a 'hammer', and neither one can be cocked except by operating the trigger through it's full cycle (cock and fire). An advantage to this system is that you can pull the trigger over and over to try to fire a misfire, which I understand usually go on the second hit. Basically, the loaded gun is an inert object until that trigger is pulled. It also has a firing pin safety which is disengaged by the trigger, so it can't fire no matter how it's hit or dropped. The P11 9mm is a pocket rocket, with a solid kick and a big fireball. They offer different height sights to adjust point of impact. The slide is relatively easy to retract to load (or unload), and the external extractor gives a raised feel with a loaded chamber. In the same size, you can also have the P40 in .40 S&W. I love the Kel Tec, as it's the only pistol I feel absolutely comfortable traveling with or carrying. If you want to shoot it every week, get another pistol for the range and save the Kel Tec for business.
Then, you have the 'hammer' pistols in double action only, double/single action and single action (cocked and locked). All are available in calibers up to .45 ACP and single-stack to double-stack magazines. Quite a field of choices. As much as I love a 1911 or Hi-Power, I just don't feel right having a cocked gun stuck down my pants, but I certainly appreciate the fact that many others do this every day.
The Tom Cat is interesting because people with a problem in racking a slide (arthritis, etc.) can load it with the flip-up barrel. I could see carrying a Walther PPK (or FEG PA-63) because they're double/single action, and the Makarov would come in there, too. I'd offer that .380 would be about the lowest power I'd want to carry. After all's said and done, I'd have to second the poster who mentioned the Taurus PT145. To have .45 ACP power, 10+1 capacity and all the safety of a Kel Tec plus a thumb safety would be hard to ignore. This pistol loaded would be a little heavier than the 9mm Kel Tec, so it's just a question of what you want - there are some great choices.