For me it's a High Standard Sentinel 22LR revolver. First gun I ever shot, and I hit what I was aiming at the first time! Dad always carried that gun on the dash of his work truck wrapped in a rag, and I was always after him to let me shoot it whenever we were in the woods (dad was a logger, so I was ALWAYS after him!

).
When dad passed away my brother and I split up his guns. There was no way I was letting my brother have that revolver!

It sits in my gun safe right now, and I'm smiling thinking about the memories!