In a tedious post-script to my American trip, I finally got an e-mail confirming my account with Bay Area FasTrak was closed.
The Bay Area is home to many of the world's biggest names in computing, and none of them were hired to build the all-electronic tolling system for the Golden Gate Bridge. You have to sign up for an account (in advance) even if you just want to pay a one-off toll for your rental car*, and then all the online settings to close the account fail to work and you have to phone them. Whereupon they can only suspend the account and cause it to close a month later.
Meanwhile, the website is terrible, and I was told it takes up to 72 hours for your crossings to show up (it's at least that). 72 hours! Clearly, somebody has to drive out to the bridge and change the tapes by hand, then bring them back for a basement full of interns to type the number plates up.
If the Americans want my advice, have a chat to the people who built the system for our Dartford Crossing. It just works, and makes yours look like the mid-90's embarassment it clearly is.
*Or you can pay the rental firm a silly number of dollars per day for the privilege of renting an electronic toll tag. But nuts to that - while tedious, this experience saved me about $50 that I spent on steak instead. Canny consumers 1, car rental firms 0.