I usually try to be slowing down the whole downhill, especially if there is a stop sign/light at the bottom. If I get most of the way down and can see it's clear, then I will start accelerating again. It's not always possible, and there have been a few hills that I did get off the bike and walk down.

Last night I almost got myself seriously hurt on the way back from the saturday night ride - there were four of us on the way back to uptown, going down a long slight downhill with stop signs every couple of blocks. Of course we were blowing all of them. About halfway down, we noticed a car on the left when we were about 10-15 feet back from the intersection. I knew I couldn't stop, so I sped up and went to the right to give myself a couple of extra milliseconds... Then I noticed there was a car in the next lane (on the right) and had to swerve back to the left halfway through the intersection. I didn't have any time to see how close the cars were, but it couldn't have been more than 20 feet.

It took me about a block to get rid of the speed I built up punching it through the intersection, and I asked everyone to slow it down when they caught up, because it took about 5 blocks for me to start breathing again.

Sometimes there is no way to stop, and adding speed is the only option. It's scary and dangerous, but it's a fact of life riding brakeless.