If you wanna go the metaphysical route and mess with people's heads, you can always get one that says "NOTACAR." But I guess most people aren't strange enough to want a plate like that.
My godfather has a 350Z with a vanity plate that says "DOGJIZ." LOL, I guess you'd have to know him, but I'll probably never get a vanity plate, because in my mind no vanity plate can ever be as cool as "DOGJIZ."
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'91 GT. BONE STOCK. Beautiful new Pepsi blue paint job.