Few hotels actually issue guests real door keys anymore and opt instead for electronic key cards, with magnetic strips on the back.
The face of the key cards often have only the name of the hotel, if that, but some hotels get quite creative with the tiny bit of real estate that guests carry around and look at multiple times during a stay.
Here are two cards I received at hotels in Portland, Oregon that morphed from keys to souvenirs in a snap.
The one on the left was issued to me at the Hotel Lucia, which has photos by Pulitzer prize-winning photographer and Oregon native David Hume Kennerly in the rooms, the hallways and public areas.
The key card on the right is from the Hotel deLuxe, which has a Golden Age of Hollywood cinema theme.
Both hotels are part of the Provenance Hotels group.