Radiators!!!
Typically, they are only "designed" in a utility sense: to maximize surface area for the purpose of better heating the air. However, I always liked to look at them as a kid & I wondered why they were so squiggly-looking! Many people cover them up with radiator covers, probably both to hide them and for safety reasons I suppose. But these ones here look pretty nice.....I say flaunt it if you got it!