On the bridges, valid carpools don't have to pay the tolls. Casual carpooling is another way to beat the traffic. There are nonprofit organizations, which exist solely to assist commuters in setting up carpools or vanpools, and in some cases providing incentives in the form of cash or gas coupons. If you're a regular commuter, you can buy commuter books to get a volume discount. Ask at the toll plaza.
Some neighborhoods are worse than others, but none are good.
Public transit and parking garages can save you some grief. Here's a map listing some Union Square parking areas . When facing downhill, turn your wheels to the right. When facing uphill on a street with a curb, turn your wheels to the left. When facing uphill on a street with no curb, turn your wheels to the right.