Hmmm... I ordered a non-M related vanity plate for my car: SKLEKTY (I'm an artist and have a character with her own website named, you guessed it, Skelekitty).
However, I'm thinking I should have gotten SIREN or SIRENA since she lures men in and then dashes them on the rocks... (Everyone I've let drive this car have become disillusioned with their own.)