So I'm cruising along at around 42 or 43 mph, about 2/3 of the way along Barren Hill Rd. when an approaching car flashes its high beams at me, five times in rapid succession. My first instinct was that either my lights weren't on, or that my high beams were on and the approaching driver didn't appreciate it.
But this didn't make any sense, as it was 4:30 in the afternoon (too early for headlights to be necessary and too early for high beams to blind anyone). My low beams were on.
Then I realized that this car was doing me a rare but invaluable favor. The flash can mean three things: fix your lights, go ahead (i.e. at a stop sign) or SLOW DOWN, there's a cop up ahead. In this instance it could only mean the last of the three, and I knew it.
It may not have been entirely necessary, as I wasn't going all that fast. But I heeded that car's warning and took it down to about 36 or 37 mph. And sure enough, about 500 feet later, there he was. A cop car sat at an angle in a driveway, ready to pounce at any moment.
So three cheers to that random stranger in the passing car. Despite the fact that this sort of maneuver is morally suspicious and clearly illegal, that driver stuck his or her neck out and saved me quite a bit of hassle, as well as possibly a speeding ticket and points on my license.
Thank you, sir or madam, for your thoughtfulness and courtesy. I hope I can return the favor someday.