I'm that guy driving like a bat out of hell in the BMW.
Whenever I see a cop I flash my lights to warn other drivers, getting a ticket is an annoyance. If I see a cop on the side of the road giving someone else a ticket I slowly drive past them in 1st gear with the engine at 5,500 revs or so as close to them as possible and then just gun it at WOT. I've only had one of them stop giving the other guy a ticket to get back on his motorcycle to follow me. He never caught up.
So far in 2006 I've gotten four speeding tickets. If I keep this pace I'll only have eight by the end of the year, not bad. The worst one was for 120km/h in a 50km/h. Those are just the tickets, not counting the times when they *tried* to give me a ticket but couldn't either because they couldn't catch me or because they could not find which law I broke and didn't know what they should ticket me for (such as drifting across an intersection.)
They've tried impounding my car twice this year already but they haven't been able to do so because they lack the authority.
Only one person has warned me of a speed trap by flashing their lights. I was doing 220km/h on a 50km/h road at night when I saw someone coming in the opposite direction flashing their lights. I slowed down immediately and sure enough, two cops were waiting for speeders a few km down the road. It was definitely a nice gesture.
It kind of sucks now though, because sometimes when the cops that I've pissed off see me they'll follow me just to make sure I'm driving like a law abiding citizen. They'll even take turns following me. Oh well, I guess its like having a police escort... kind of.