Probably a gun I own now -- a Cobray M12 in .380. Jams with anything but factory mags, tends to pop an e-ring off one of the pivot pins, and it's built like a cheap canteen.
I love it anyway. It looks like a MAC-10 that smoked when it was little. I got a big fake suppressor for it, and now it's the baddest-LOOKING gun I own. The very definition of a "fun gun," and besides, I'm a .380 guy -- I have a half dozen of 'em and about a thousand rounds of ammo. This one's a rarity in the caliber, and I'm glad I have it.
The only guns I own are in .380, 22lr, and 7.62x39. Keeps my ammo needs simple.
"Valor needs first strength, then a weapon."
-- J. R. R. Tolkien (1892-1973)
"Free men have arms; slaves do not."
-- William Blackstone (1723-1780)