I read about some group or club ( I think of highly obsessive people lol) that do this for fun or entertainment. I think they even have competitions and meetings and stuff.....cant remember what they were called...There IS a term for them...
read an article like that. They park on hills, etc. so they can get rolling starts, shut the car off on coasts, coast a lot longer than they really should, obsessively time lights, I think they're called hypermilagers or something?
I actually did this recently. I'm used to driving on the freeway at about 75 or so, and usually get 17-18 in my f250. This last tank, I did 65, and wound up with 22mpg