Where did the word pimp originate? Are there any related words?
The OED says:
The legend is that it’s an acronym for “Procurement For Immoral Purposes,” although like For Unlawful Carnal Knowledge, no one seriously believes that’s the true etymology.
–Cliffy
Good ol’ etymoline echoes the OED, more or less. The OED should probably update it’s definition pretty soon too, considering the drastic connotation changes that’ve gone on with this word. I mean, I saw a little kid, probably 5 or 6, on the bus last week wearing a shirt that said “Future Pimp.” A little disturbing. “Pimp” has gone from a word associated always with its meaning (read: guy with harem) to basically meaning anything that’s extravagant, a little excessive, souped up, or exceedingly cool. The only other word I can think of, ironically, that’s undergone a similar change lately (in both connotation and acceptance) is “bitch.” I’m sure something can be read into this, it’s just too early for me.
You left out having shiny wheels taller than the vehicle, a radio that can be heard three miles away, a cell phone permanently connected to the ear, and the inability to whisper or speak softly.
Birdmonster, I think a case can be made for another word; it starts with N.
As to the cause, let us assume that it’s because kids are dumb. 
–Cliffy
True, true. I tread lightly in those alleys.
Of course, as for the kid with the “future pimp” shirt: he was 5. Maybe 6. Mom definately bought that one for him. So, we can assume that mom (or dad) is dumb. But that’s not exactly a revelation.