Well, I've had to live through a bicycle-vehicular collision. I was on the bicycle, and my elbow was fractured! Not a good thing. I ride my bike like I drive my car - defensively. When the situation dictates, I ride more to the left if possible (ie riding along parked cars where someone may give you a "door prize" at any moment).
If I'm driving in the right hand lane, and there is a cyclist in front of me, I always pull around the cyclist as if they were another vehicle in that lane. I always check my rearview/side views when I pass them -- especially if I'm stopped at a lite, because amost 90% of the time the cyclist will catch up to traffic at the light and some unobservant driver is going to pull into their lane and hit them -- that's sorta what happened to me.
Anywayz, I've got a pin in my elbow and a lovely scar with staple marks to show what an idiot driving on the wrong side of the road can do to a cyclist. Not fun.