The '89 quake changed Bay Area transportation in significant ways. Most importantly, the natural disaster highlighted the vulnerability of so much public investment in a single form of transportation (namely roads and highways).
Earthquake retrospectives have dominated the news in the Bay Area over this past week. One story that stuck out for me was that of a Los Gatos family who took over half an hour to drive three miles on wrecked roads. I fully expect even bicycling to be disrupted, but it's possible to carry a bike over obstacles -- something I cannot do with a car.
My dad was an executive for Motorola in Japan when the 1995 Kobe earthquake hit. He led one of the very first rescue teams to arrive in the devastated zone because he and his team used bicycles to haul relief supplies and portable ceullular base stations into Kobe. I reported previously that many emergency response plans call for the use of bicycle messengers if electronic communication is not available.
If you're inside a bike shop when a quake hits, however, it might be a good idea to run away if this security video inside InCycle bike shop in Chino, California is any indication. This occurred during the 5.4 quake in July 2008.