Good replies, here's my two øre: I "ride like a car" if at all possible, but it does depend on the speed of the other traffic. If I'm *significantly* slower, I would try to stay out of the way and maybe use a pedestrian crossing. If I'm just a bit slower I'll take the lane, make huge obvious hand signals, and make an effort to accelerate fast out of a stop.
I'll pass a line of cars standing still if I can see there's room for me at the front or side, but I always stop where I'm most visible to the closest car, usually just in front and to the right of them. I never pass cars on the right if they're moving or I suspect they'll start moving while I'm passing. In other words I only go to the front of a line at intersections I know well, and then I'll usually sneak ahead as far as I can ahead of the line, so that I will be the first "vehicle" across the intersection. This is the only traffic rule I tend to bend. Passing someone in an intersection isn't allowed here, so I do my best to be all the way past the intersection and over to the side before someone needs to pass me.
Winter riding is much less about badassery and much more about bundle-uppery. - malkin
1995 Kona Cinder Cone commuterFrankenbike/Selle Italia SLR Lady Gel Flow
2008 white Nakamura Summit Custom mtb/Terry Falcon X
2000 Schwinn Fastback Comp road bike/Specialized Jett