My mates had a big 4 bed house share at uni and we started with scalextric but got bored of it so we floored out the attic and installed a radio control car track in it and raced mini mardaves around it.

Was a proper nerds paradise.
I even wrote some crude computer software to allow us to design different track layouts based on where the access harch was and where the beams were etc.

Sadly no pictures though as was 20 years ago and didnt have such things as digital cameras etc at the time.