Not as a slam on mouse guns--well maybe a little 
.
I keep hearing the words "cool" and "concealable" and "little."
I like words like "shootability" and "accurate" and "handles well" and "fits the hand."
Cool and consealable are "not" words that I use to describe a CCW.
My p220 Sig is concealable and findable.
Small has no definable characteristic of a CCW in my opinion--especially "mouse."
Blessings
LOL.
I agree.
A Sig P22_ Series is a whole lot better than any mouse gun.
My P230 while smaller I do not think of as a mouse gun.
I consider it and other 380's of medium frame on par with a J frame in 38 Spl.  So Colt 1903 / 1908, Beretta Cheata, Walther PP,PPK/S
I think Mouse guns have a place and a purpose.
I think there is a difference between a Mouse gun and a Novelty.
I think a Walther TPH, Colt pocket in .25, SeaCamp (and Copies in .32), S&W I frame & Beretta tip barrels are mouse guns. Not sure if a Walther PPK fits this catagory or the above. 
The idea of a novelty gun is cute.  I do not find them practicle.  That little revolver in 22LR while neat is not practicle.  They are too small to manipulate well and make multiple hits quickly.  At least for me.  I saw the little derringer I had the same way.  While neat it was not practicle to conceal, draw, arm (set the hammer and take off the safety) and aim in a fluid movement.  That short fluid movement that would be needed to defend your self.
I also think your age, activity, and climate may dictate the need for a mouse or pocket gun.
The older I get the less I go out in sweats.  The TPH can sit in the pocket of the sweats, but my Sig P230, or Det Spl send them strait to the floor.  I am not one that wears my draws around my thighs.  Moving from Southern Ca where anything more than shorts and a polo out for a walk in the summer with the mutt would stand out, a full frame is not practicle.  A pocket or mouse gun is.  Also the threat to me with the Dog are not going to be two legged.  No one will try to attack me with a large dog at my side.  My concerns would be other dogs, and wild life like Coyotes or rattle snakes.  I need a gun that I can carry based on condition, climate, and be able to hit things like a snake from 15'. 
Now that I live in Northern CA on the coast I wear more clothes and a walk today would include a jacket.  It is 57 degrees at 8:30 am and foggy.  My jacket can easily hold a meduim frame auto, J, K, or L Frame 2 or 3" revolver, even my Sig P-229 can slip into my field coat hand warmer pocket and not show.  Also on this side of 40 I do not go jogging any more but longer walks where a heavier caliber and larger gun is more practicle in jean or khakis rather than sweats that are capible of holding a pocket or full sized gun.  If i were to mover back to the deserts of Southern CA or go to a friends house in the central valley in summer where temperatures soar over 90, I would want my mouse gun rather than no gun.  I also know I can make multiple hits in an attacker's face quickly.  To stop them from doing what I thought was a threat to my life.