A way to save energy (a.k.a. $$): It's laundry day, and the drier heats up the clothes and blows some air around. It's a lot like summertime, really. A clothes line can help your beloved shirts last longer--the elastic won't degrade from the drier's heat, they fabric won't get worn out from agitation, and everything will have a fresh scent. Make sure to turn T-shirts inside out so the sun won't fade them prematurely (wash T-shirts inside out too).
I especially like the very slightly stiffer way clothes feel after they've been hung on lines.