I'd ordered a yogitoes skidless towel but the place I ordered it from was out of stock so had to cancel the order. Shame, Kino uses one in her DVD and it looks great and doesn't appear to bunch up. Almost impossible to find them in the UK. I am, however, expecting delivery of a Manduka Equa any day, but until then here's what I've been using.
Yoga towels are made of microfiber so pick up a cheap microfiber towel from eBay. Try to find an XXL one. Cut it down the middle, fold the cut edge slightly over and use a straight forward blanket stitch and there you have it. Two non slip yoga towels that work, for half the price of a branded one. Great absorbency and they dry really quickly too.