Actually, they're not a bit smaller, they're a whole lot smaller. Here, at about actual size, is the Xythos revolver in comparison to my High Standard derringer:
This is the wonderful and wacky world of pinfire blank-firing micro "guns". The following pictures are magnified images, because the things are too darn tiny to show life-size. The quarter is there to help keep things in perspective.
I picked up the revolver at a gun show, just for kicks. It's advertised as a flare-gun survival item when assembled in this configuration.
I suppose if you didn't really need to launch flares, you could cut off a bit more of the barrel, increasing concealability :)
The Maus (German for "mouse") was given to me by my aunt ages ago, when she found it in the back of a kitchen cabinet in the house she had just moved in to. This must have been the deluxe model, complete with fitted box, ramrod, and pinfire blanks in gelatin medicine capsules.
Reloading is tricky, because you really need some fine-point tweezers to handle the ammo. Here are the two "devices" (I hate to call them "weapons", although I'm sure TSA would take a dim view of trying to take them aboard a plane) broken open, and ready for loading.
The cylinder pin of the revolver is unscrewed (via some teeny tiny threads) to allow the frame to break open. The front half of the cylinder is removed, and the pin is then used to push out the fired blanks. There are seven holes in the cylinder, but one is an alignment pin that joins the front and rear halves together.
I fired one shot with the Maus, and the bang was surprisingly loud, about like a full-power cap gun. For you folks under 40, I will not explain what a cap gun is. You can research it on Google, and learn about all the depraved toys we were allowed to have back then.
Next week the subject will be about something bigger, because I don't think I can go smaller than this.