Speaking of laws to be obeyed, and introducing THAT subject (you know, the one we've ALL been waiting for) hi-viz vests.
On PBP 2011, I saw, with my very own fatigue-free eyes, riders being pulled over (and maybe even fined) for, as it transpired, not wearing hi-viz. I wasn't wearing mine at the time either, because I didn't want to stop to put it on, but quickly rectified that.
It was still light but fading... dusk as they say I guess.