Felix has a great story about Sierra Road, the 3.8 mile, 1800 feet climb that pro cyclists raced up earlier this week during Stage 2 of the Tour of California. Having discovered the painful pleasures that is Redwood Gulch Road, I shudder at the thought of a climb twice and long and steeper!
My winter hiberation is nearing an end. I expect to be back in the saddle and shedding Calories shortly!
tow.com 
Hi Adam! I have heard about Redwood Gulch from a couple of people, and actually, from the sound of it, I suspect it is even steeper than Sierra. Like you say, however, it is not as long. I wish I had gone up it at one point just to gauge whether it is more difficult than Sierra or not.
Another good climb to do is Jamison Creek Road on your side of the bay. It is a little shorter than Sierra, but more sustained. You can read my review of the Santa Cruz Mountain Challenge for more info about that one!
Felix:
Here’s a grade readout of Redwood Gulch: http://graphics.stanford.edu/~lucasp/grade/redwoodgulch.html
Max Grade 18% with average grade of 9.7%
Ouch! 18% (or 21% in a turn) will definitely hurt towards the latter part of a 1.4 mile climb. But yes, sounds quite short compared to Sierra ;)