Kapa Designs Adjustable Solid Brass Ring, around $10, etsy.com
If your ponytail is starting to feel more lazy than laissez-faire, take a cue from Dries Van Noten's Fall 2011 runway and wrap a sleek ring around it. Use your regular snag-free elastic, then twist your hair as tight as you can and work an adjustable ring from the bottom of your pony up to the elastic. I've found a bunch of under-$15 versions at ALDO Accessories and Forever 21 but this solid brass ring from Etsy is my absolute fave. Genius!