Not a clock, but i did rattle one of my wife's tennis trophies off the shelf.. It was a solid glass, tennis ball shaped thing and it fell 5 feet off a shelf.
Good thing my camera bag was on the floor under it and caught it unscathed!
I rattled one of my wife's glass candle holders off the mantle one time. I glued it back together, and she didn't notice for a long time;but, she did finally notice...
I was testing out some cabs a few days ago. I had a few 2x12s with various new eminence speakers in them and they were meant to have heavy bass.
Finally I switched to a 2x10 fane cabinet from late 70s selmer (I bought for about $100 here in europe, steal!) and hitting one note made the garage door nearly fall off. Insane amount of bass - but perfectly balanced when playing just like fanes should be And people think 10s are going to be wimpy.... hardly!