My personal experience of driving south from ~San Francisco down to Sunnyvale along 101 in the mornings is that it takes me around 1.2 hours, on average. I'm not sure what traffic maps have to say about it, but every time I drive down I hit backups at Millbrae, San Mateo around 92, Menlo Park (the Facebook exit), Palo Alto which is just always congested, and Mountain View.

In fact, the traffic is the deciding factor for me in ruling out regularly working in the Peninsula.

Where do you start, and at what time of day, to get 20-minute drive times? I'd love to know the secret.