I commute 18 miles one way, then I take the bus home, but that's another 4 miles from my job, so grand total of 22 miles. Ride in takes about 1.5 hours, because of traffic lights, stop signs, and hills. I do this 2 or 3 times a week in season (not when it gets cold or the days are short, since I hate biking in the semi-dark...) I love love love the ride in, much of it in the countryside with little traffic-- I've seen deer, pheasants, grouse, and all manner of small wildlife on my commute, I listen to the birds, I used to listen to my iPod but I sort of got away from that, just like to think & enjoy the ride. I wear bike clothes because I get all sweaty but fortunately there's a shower at my workplace.
I plan to take early retirement next year and work at home. The only downside to that, I see, is that I won't be able to commute to work!