During Loma Prieta I got maybe 15 secs of warning ... driving in Berkeley I heard the announcer on KQED (NPR affiliate in SF) say something like "shit earthquake" followed by dead air ... time to stop the car and see it ripple up the street

(normally on that day of the week I would have been on the lower part of the freeway that collapsed, went into work a day early that week because of the possible World Series traffic)