When I was looking for pocket pistols, I narrowed it to .32 or .380 ACP. Kel Tec's .32 is super light and can be one of best pocket guns in the world if only they would update the design with better sights and a better trigger. Maybe if they'd steal a play from the Ruger book, make it a striker fired pistol and call it the P-32s.
The other .32 that I would consider, even though the price is a bit more than I like, is the NAA Guardian. Slightly heavier than most of the smallest/lightest .380's due to its all stainless construction, it has to be a dream to shoot the light recoiling .32 from it. The size is insanely small too, unlike the larger .380 version of the Guardian, which I would pass on.
For .380's it came down to the Ruger LCP and the Kahr CW380. IMO a pocket gun should be polymer framed to reduce weight and resist moisture. I don't think Taurus TCP is worth the price because I think you can get much better for a little more and because Taurus customer service is infamous for being very poor.
I think the S&W Bodyguard has so many switches and safeties on the thing it gets disqualified from being considered a pocket gun. It's more of a shoulder holster or IWB gun.
The Beretta Pico sucks.
The Bersa Thunder is too big for a pocket, imo. A good gun tho. Same for Walther PPK.
The DB380 is not reliable.
So, all those contenders eliminated, it leaves Ruger's LCP and Kahr's CW380 (don't spend the money on the P380, it gives you literally nothing extra over thee CW380.) Now that the new Ruger LCP II is out, I consider it a top choice, although I think the LCP Custom is better, you'll A. never find one and B. Never find one for a lower price than the LCP II. The Kahr is also a good choice because it's so darn small. The sights are good, and the trigger's are crisp, but the only think I wonder about is the magazines as I've heard some negative things about the factory mag performance.
One thing to note about the LCP is you can buy 10 and 15 round extended mags from Promag and the 10 rounders work very well and are not so large as to be a joke to carry for a spare mag. The 15 rd mag is... silly.