The discussion of Penn Station (http://www.slate.com/id/2246104/ http://www.slate.com/id/2246104/) in the same series has more concrete examples, and is pretty

The discussion of Penn Station (http://www.slate.com/id/2246104/ http://www.slate.com/id/2246104/) in the same series has more concrete examples, and is pretty cool if you've spent time in Penn.