Human Events has a very nice read on this subject. They have put together a "best of breed" look at .22 and .32 caliber pocket guns. It is a Part 1 with a .380 write up coming soon. They also talk a bit about pocket carry in general.
Now, I agree with just about everyone of their picks except for that darn NAA Mini. Simply put... Those little suckers are really hard to shoot. Yes, the grip on the Pug does make it considerably easier, but I would not look to one of these to ever be anything more then a novelty. That being said... the other side of the coin is that I have seen a good number of news stories over the years where in an attacker/home invasion was stopped by elderly gentlemen who happened to have had one of those NAA Minis in their pocket. Yes, there is a lot to be said about the "first rule of a gun fight".