Probably my Hasselblad. Only because I thought I'd never be able to afford to own one, and I managed to find one for $500 that was LNIB, including the boxes, and from a very nice woman with a very touching story. She knew the value of the camera but she just really wanted to see someone get happiness from it. Total stranger but she gave me a big hug and cried before I left. It was apparently her late husband's prized camera.
I will never sell that camera no matter what.