Den Tek has the best dental floss picks I've ever come across. If you go to Den Tek's website, you can print a $1 off coupon for their dental floss picks ($2 or more) from SmartSource.com (the coupon will print immediately after clicking the coupon link on the website, so be sure your printer is ready). Retail for a pack of 90 dental floss picks is around $3.29.
If you happen to use dental guards, they have a $3 off coupon for those as well. You might want to sign up to receive coupons and free samples via snail mail. As to which of the two - coupons or samples - you'll actually get, the sign-up confirmation is a bit vague on. But who cares? Who can pass up free stuff?!?!