Commuting by bus in not particularly fun (I assume that that is what you mean, though I'm not sure) but it wouldn't've been any more fun with a Macbook Air than a Mac mini: they weigh about the same, but if I had carried an Air I would have had to carry a charger or buy a second charger to keep at the girlfriend's house. And of course the Air costs more (even after accounting for the cost of the extra monitor, keyboard and mouse I kept at her house).