Here's a little joke I play on some people when they start harping about how a .22 is worthless for self defense. Now, that being said, I realize a .22 IS inadequate in the case of an assailant who is pointing a gun at you and is pulling the trigger.
That being said, I sometimes mention that in many scenarios I could easily use my trusty old Taurus 9-shot .22 double action revolver for self defense. That sometimes brings a big laugh of ridicule. I make it clear that I've had the gun about 30 years and have fired probably 100,000 rounds through it:
"Tell you what, I'll make a deal with you. I'll put... $50 million cash on my dining table, and stand in front of it with my .22. You come in the front door over there, about 25 feet away. If you can touch the money, you can have it. Deal?"
So far, nobody's taken me up on it yet. A few months ago I pulled this on a SWAT cop in a gun shop. He was a big, ugly, shaved-headed guy in full combat dress. When he said "naw, no deal..." his buddies started laughing at him - no hard feelings, it was all in fun. It was hilarious.