Fun with Google Maps
If you know you want to avoid certain roads and/or highways, you can simply drag your route away from the undesired route and the directions are re-calculated! Way cool!
For example, I wanted to avoid getting on the highway to get to South Park, so I dragged the point that instructs me to get on 101 over to Van Ness, and a new route was planned out on the fly!
Also, I just noticed the “Avoid Highways” checkbox. Sweet! I had always used Mapquest for this in the past.