Another story I heard was that Drake robbed a galleon in the area, and was awash with the loot. He stashed the loot he couldn't carry, like china and silver somewhere on the California coast, and took only the most valuable stuff, like gold and jewels. Bits and pieces have been washing up for years.
This may interest you.
http://www.freerepublic.com/focus/f-chat/1794543/posts
Pirates....Arrrrgggghhhh!