Good idea:  Driving with your headlights on at night.

Bad idea:  Driving a ratty 17-year-old Nissan, possessed with the spirit of a decrepit old man, that has an electrical bug that causes your dashboard, console, and tail lights not to come on, leading YOU the DRIVER to not notice that you are driving after dark with no headlights.

As I discovered today, the police generally frown upon this kind of behavior.  But...

I was obeying the speed limit. (I had only just pulled out of a parking lot.)  The policeman didn't see my non-functional tail lights, just the fact my headlights weren't on.  (Whew.)  I hadn't gotten a ticket in my entire year and a half of bein a licensed driver.

So I got away with a "Promise to keep your lights on while you're driving for the rest of the night," followed by an immediate "Yes sir."