Actually I have several... I'll only relate two.
Waxing my car when the big Coalinga quake hit. I was bent over waxing the bottom panel of the door when I realized that the car was waxing itself. That struck me as odd. I looked up and saw the wall of my shop waving, like ocean waves... that was definitely a sign of something amiss.
Second tale... that same night, or maybe the night after, friend and I went to my ranch in Coalinga to hunt. On the way we stopped at Harris Ranch, and imbibed. Left at 2am... well imbibed. Got to our ranch and threw our sleeping bags on some cots that were on a tile floor over concrete. No padding... about 5am we were woken when my friends cot and my cot were engaged in combat... ramming into each other. We put two and two together... world's worst hangover. But ahhh, twasn't a hangover... it was an aftershock.
On the way into our ranch, (about 4 miles), it was dark so we noticed nothing unusual... so yeah, even if it had been daylight we wouldn't haven't noticed anything unusual... remember the 'imbibing part'? But the morning of the aftershock, now sober, sort of sober... we noticed something unusual, several somethings in fact.
Chunks off mountains the size of large homes had broken off and careened down the mountainsides..... everywhere. Not from the aftershock, (we don't think), but the big Coalinga quake.
One chunk stuck into the mountain side at an odd angle... and looks like it should fall over and continue down the mountain... but it hasn't, yet. Still there today.