Ideas seem to be running pretty simple lately..
Think of something that would be impossible to build. And try and build it :D
Anyways, I've always wanted to see a Russian style built, with the tear drop roof things :P
An underground city could be interesting, maybe even an underwater build lol. Maybe even a city thats designed large enough you can actually have some sweet street races in, think need for speed, then you just set up different pilon Combinations to make different tracks, with secret paths, jumps and such.
I always wondered if someone would build that actual inside of a computer, big enough that a small city could be built inside :P
on a side note, Can anyone build good statues? like large scale. I'm just wondering, cause a statue of liberty, or different roman statues could really add to a modern/roman city style :)