I commute in Atlanta Georgia, typically riding 20 miles from Decatur to Sandy Springs. The most direct route is 15 miles and I never do that one. That route has me spending well over half the distance on major four to six lane roads with 45 mph speed limit and lots of agressive traffic and narrow lanes. Not my cup of tea. My route mostly follows neighborhood roads where few if any drivers would drive as thru-traffic. The roads are almost all two lane with 35 mph or 25 mph speed limits.

I have a few favorite routes and then one in particular that I ride 90% of the time or more. Among other benefits I find that routes with a lot of turns make the time go faster. I get a better feeling of progress that way. And the ride goes through more "phases" in terms of the kind of surroundings (industrial, parks, suburbs, etc.). While I love to follow routes like these, I sort of dislike learning them. I don't want the mental focus that takes while I ride. I like to ride without figuring out how to get there. So I've developed most routes for commuting/other by using the TomTom app on my iPhone which finds great bicycle routes. It will do things like route me through a shopping center parking lot as a way of getting between two streets expediously. Or it might send me on walking bridge over the interstate - in short, things a car driver would not or could not do but work great on a bicycle.