Bwwwwaaaaahahahahahaha!
It's not an envelope, it's a miniature diagram of a famous painting that you should know the name of, but you can't put your finger on it.
No, wait, it's a floor plan for the hotel rooms at this year's TCIA.
Oh, wait! It's an album cover from the 80's... The Cars, Heartbeat City maybe?
Or maybe it's something more...