this may be a very old joke / tale, but....
as the story goes some guy has a nicely kept karmen ghia with the plate "TIMS MG"
when people tell him "that's not an MG" he says :yeah, and I'm not Tim".

right now there's a 1997 car in my shop with just over 15k miles on it, the plate is "NETFLIX".

I think my favorite belongs to a customer, a pro photographer that tells me he feels like he "sold out" and isn't really doing the work he likes or respects. his plate : "FODOHO"