I had a "kaboom" last night. Of course I've heard about this, but I didn't expect that it would ever happen to me. I had positioned my Canonet G-III on the table and was taking a timer picture when it went off. Evidently this is caused by gases that build up in the camera from old film. Then you get a little spark from a loose meter wire or something and ... blam-ooo!!!
Sounded like a gunshot. My upstairs neighbor came down to see what had happened. She couldn't believe it when I told her.