The first and last 1/3 mile of my commute is down a cruddy old gravel country road. With this sort of road, going uber slow seems to only make the bumpiness feel even worse (also, going very slowly through very loose patches of dirt/gravel=very good way to crash). I generally try to keep a moderate pace (around 12 mph) and steer for the parts of the road that have the smaller, finer rocks and avoid the parts that have the big, bumpy rocks.

For the urban section of my commute, there aren't too many stretches of bad road; one stretch is about a mile from work and is heavily trafficked, and luckily all the bumps are near the right side of the lane, so I veer to the left and "take the lane" for that stretch (undoubtedly to the chagrin of the cars behind me).

As far as advice, I offer this: If I were on a low-traffic road, I would probably veer onto the other side of the road if necessary to avoid a bump. If you have to hit a bump, grip the handlebars only firmly enough to keep control of the bicycle, but don't grip them like a jackhammer (unless you want your arms to feel like they just got hit with a jackhammer). Standing on the pedals might not be the greatest idea because it gives you only four points of contact with the bike and may make your position less stable than if you were to remain seated amd have five points of contact. Finally, make sure your tires are adequately inflated in order to avoid pinch flats when your tires do encounter jagged pavement.