|I've had several projects lately that needed serious first aid and I found it at Walgreen's: the humble Ace Bandage or its store brand counterpart. I've used the 2" and 3" ones to add more oooomph to flabby ribbing on the hem of a polo shirt, add weightless layer of elastic to the tummy band on a pair of yoga pants, and fix the saggy, too-large gathered collar on a knit shirt. It's easy to sew through, and is very subtle - a kinder, gentler version of elastic. It probably won't last as long as regular elastic, and a reasonable, careful person would make an attempt to keep these things out of the dryer. I am not that person, and I figure that the worst thing that could happen is that over time, the elastic begins to wilt and I'm left with the a garment with the original problem. But in the mean time, I've got comfortable, invisible elasticity where I need it.