This may be one of the coolest things I have ever seen.
Most train stations have a room with lockers where you can store your luggage for a few hours. Köln’s Bahnhof has a row of automated machines that fill the same role.
It’s coin operated. You select either ten or 24 hours and pay accordingly, then you put your bag in a metal cube and a conveyer belt whisks it away to the underground land of gnomes and cookie dough. When you come back later in the day, you give the machine your magnetic stripe receipt and it retrieves your bag from the Keebler Elves and sends it back to you via conveyer belt.
This is so cool that I may need to lie down.