When hotels and motels still used metal keys, they regularly came attached to large plastic key tags that listed not only the hotel’s name and address, but also the room number of the key holder. They also included a “Guaranteed Postage Paid” stamp, so that guests who absentmindedly walked away with the key could drop it into any mailbox the next time they emptied their pockets. Today's computerized key cards provide guests with an extra safety measure: they are re-keyed after every check-out, making it impossible for any random person (or former guest who held onto a key) to enter the room.
One of the most welcome sights after a long day of driving was a colorful, twinkling, blinking sign offering a comfy bed (along with other amenities) for the night. Googie architecture, a futuristic style inspired by the Space Race, was popular in the 1950s and '60s. Buildings had bold, curving, geometric shapes and their signs were bursting with mutlicolored neon parabolas, boomerangs, and starbursts. Holiday Inn was famous for its dazzling Great Sign, which the chain sadly retired in 1982. Much like the old Best Western signs, it was a bit of Las Vegas perched on a signpost, but most chains have since eschewed glitz in favor of more subdued, “sophisticated” signage.
Another previously common feature of yesteryear that has since been recognized as a possible security hazard is the large key cubby that used to hang on the wall behind every hotel front desk. Whenever a patron left the building, it was customary for him or her to leave the room key with the desk clerk. That way the front desk staff could tell at a glance who was in their room and who wasn’t so that they could take messages (which were also left in the cubbies) or, in case of a general emergency, know how many patrons to evacuate. Again, nefarious types were able to use this obvious visual clue to rifle through unoccupied rooms (hey, they were nefarious, that’s why they could easily break into a hotel room unnoticed), so it’s probably best that this type of red flag is no longer publicly posted.
To escape from predators, flies have evolved a highly aerobatic flying style. Instead of turning by flapping harder with one wing than the other, they roll their body to one side and pull up, like a fighter pilot in a high-G turn. Random zig-zags like this make it much harder for birds to get a 'missile lock' on them.