Currently mine is a toss up between two Ruger Single Six's.
One my father gave me for Christmas a couple years ago, my first "I own this" pistol. Has the .22/.22magnum conversion cylinder. Shoots great, feels great, looks great, and it's from my pops.
Tied is a Single Six he passed on to me from his father. It's an old style from the one year they made them with a flat backed ejection port cover. Pretty pistol, but it tells a funny story in that apparently Grand dad thought himself a cowboy and would "mess around" with this little 6 shooter. He tried to etch his initials into it, apparently used it as a hammer, and put a hole in some furniture when he was playing "Cowboy" quick draw with it. It's a wonderful mix of "Dang grand dad, why did you jack up this rare and beautiful Ruger." And "Thanks for the funny story's around this still awesome little pistol." I don't swear the cosmetic stuff on it because it will probably be one of the two that are pried out of my cold dead hands.