big patch of floor, i find the old sytle excercises have the most effect. push ups, sit ups, squats, kicks, punches, I can get a great workout with no equipement at all, and I love it. (I do have everything at home from cross trainer, treadmill, weights.. etc) but at the end of the day its my lounge room floor space and maybe my joggers for a walk or run outside. (I also love yoga, so a good yoga book to take you through the basics)
what didn't work.. any of those tv miracle machines (ab circle pro, .. blah blah)...
I used to get suckered in all the time