Camptown Ladies are infamous for singing it.
On the road most of the day, saw a few that were clearly names or initials, not very interesting.
But… Honda Odyssey with SOULMAZ. It’s a short stretch to imagine Soul Mates.
And a BMW 440i coupe with NYSOMND. California plates, so someone who’s really missing their home town? And/or a Billy Joel fan?
RIBBITT on a dark green Mini Cooper.
GYPCIS on a Range Rover with Montana plates. Gypsies I guess? They are pretty nomadic if they drove here from Montana.
KOOL KRW on a Jeep. I’ll give them the benefit of the doubt that their crew is cool.
ZINGQ on a Lincoln Navigator SUV. No clue.
And spotted in the office parking lot at lunch time:
KRANTIP on an F150. “Kran tip”? “Krant IP”?
And last night I spotted:
6MERAZ on a black Mercedes with dark tinted windows. I can’t decode that one.
KOOKIE on a Hyundai Elantra. I assume a funny spelling of either “cookie” or “kooky”.
DM BGGE on something forgettable because I don’t remember. I couldn’t decipher it last night, but as I was typing it this morning “dime baggie” popped into my head. If that’s it I’m surprised it got past the censors, even if weed is legal here.
SACTOAS on a Tesla. “Sacto” is a common nickname for Sacramento, but I don’t know what the AS means. Maybe just literally the word “as” ane it means something like “I’m Sacto as… something”
I’ve mentioned previously in this thread that the streets in my addition are under construction and there’s been a lot of people parking on the streets that aren’t torn up. This morning I saw BTRFLY on a car parked on the street that had a bunch of flower decals on it.
ONOSMOG on a Tesla, probably self explanatory.
KT LOU on a Jeep. I’m guessing the owners’ names are Katie and Lou, or possibly the owner’s initials are K.T. and last name Lou. Or a woman with two first names – Katie Lou, but that strikes me as less likely since Lou isn’t generally a feminine name.
Saw this one again this morning and realized it’s actually spelled RIBIITT. Not that it changes the meaning.
HNY BABA on a 4Runner. “Honey Baby” I presume. Or maybe it’s pronounced “bay bay”.
YEPPERS on a Chrysler Pacifica minivan with Idaho plates.
DDDMMM No idea
CRDPNT On an Arizona Cardinals plate. Punt? Point? Pint? Paint?
This morning I spotted a plate that simply read J46, on some crossover, I think maybe a Subaru. I assume that means something to someone, but it’s completely cryptic to me.
A BMW 4-series sedan with FLEX428. Notre Dame / Fighting Irish license plate frame. No other markings. A quick search reveals that Dunlop/Tortex makes a Flex 428 guitar pick. Maybe a devotee?
BIG BETZ on a shiny new Jeep… maybe a professional poker player?
HAIL MRY on something small, black, and sporty with a Green Bay Packers license plate frame. I’m assuming football, not the Lord’s Prayer.
Or the movie but that seems ephemeral for a license plate.
QUENBE3 on a VW ID.4. Probably self explanatory.
On a little econobox that zipped by me on the freeway: DRGNSPK. Dragon speak?
And on a Jeep Wrangler: COONDGS. I’m guessing a fan of hunting hounds.
Or the book… but after this thread I’m not sure anything is too ephemeral for a license plate. 
This morning I saw TATONKA on a Jeep that can only be described as “baby poop green”. No clue what the plate would mean.
And then on the way home I saw something that’s gotta be some sort of weird coincidence. There were two identical (as far as I could tell) white Teslas in the lane next to me. One of them had what I figure are standard issue Texas plates, black print on a white plate. Texas plates aren’t all that common in Indiana so that was unusual to begin with. The other Tesla had an Indiana plate that read ODESSA1… Odessa being a city in Texas… Could have been nothing but who knows.
C8FFEE on a first responders plate. Coffee but both O and 0 were already taken.
3YSHUA Google’s AI suggests the holy trinity (Father, Son, and Holy Ghost) , or Volume 3 of some study materials, or a three hour(!) immersion worship.
A few from the last few evenings:
SNOW97X on… a Lexus sedan. That would make sense on a Saab 9-7X that the owner used to drive up to the ski slopes. Maybe that was their previous car, and they just kept the same plate when they got the Lexus, and now it means “[it]'s no 9-7X”.
SPLWAV on a California Arts Council plate on a BMW 3-series. “Spill wave”? “Splash wave”? The Arts Council plate is a “palm trees and beaches” motif, so I’m thinking something beach/ocean related.
EDDGARR on a Ford Escape. I guess “Edgar” with some extra letters.