The Oakland (OAK) VOR has been out of service for quite awhile, most recently extended to 31OCT10. This is an interesting backstory of why the VOR was taken out of service, and what they are doing to fix it.
OAK is also used for certain procedures at SFO, notably an engine-out procedure to remain clear of terrain in IMC. Most large airplanes are now equipped with VNAV and LNAV systems that do not require a specific navaid to be received. In the past, a VOR closure like OAK would then change the engine-out profile. Now, with the level of navigation performance onboard, that no longer is necessary.
