Building competition: What theme would you like?

We have a few building competitions each year for members to show off their talents while building to a common theme.
Please make some suggestions for what theme you'd like to work with, and hopefully we will be able to start a competition soon!
Some previous themes: High Fantasy, Railway Stations, 16x16 chunk, Brutalist.
Plot size will be 75x75.
Comments
Fire and Ice
Any more theme suggestions?
1950's Sci Fi Retro Futuristic/ Quasi Jetsons.
^ I like Shtogie's! Retro space age!
stogie's is good^^
I like the idea of Retro stuff!
Hey 4 people is better than zero people.
I also like the idea of retro futuristic btw
Yes I have a Shirecraft Youtube video to plan around a competition, let's go
@EnderKilla @Hay
is it retro space age
Ooo nice, ok :)