Check out Russian Sam's amazing model of Tulsa. He creates each building using Microsoft Paint, at a scale of 10 pixels = 1 meter... no kidding. He prints the images on regular printer paper, cuts, & assembles. The whole model is probably less than 18" square, and only weighs a few ounces.

http://www.skyscrapercity.com/showthread.php?t=1206717
http://www.flickr.com/photos/4453322...7627920726581/
http://www.youtube.com/watch?v=U7GTdDV16kc