74.4 Miles.
Each way. 2.5 Hours One Way, 5 Hours a day. 3 Days a Week. Yes, that's 15 hours of commuting a week. Most of it is on the bus, though, not a lot of driving.
http://www.youtube.com/watch?v=sSApqNJP46o12 Years now, with one two-year break 2002-2003.
I make - literally - 5 times as much, doing the same thing, in New York City, as I can ANYWHERE else.
The vast majority of my work involves research and writing, so of my work week, I spend 10 on the bus working (the other 5 are getting to and from the bus), 18 in the New York office, and 16 in the home office.
The laptop broadband cards are a wonderful, wonderful invention for the extreme commuter.
If you are a "knowledge worker" and you do most of your work with your head and a keyboard, extreme commuting via mass transit can be some of the most productive time of your day.