On Amazon right now you can get this fun Aqua Leisure Ind AW-4152 Triangular Snow Tube, 48-In for just $13.09 when you clip the $1 off coupon. This looks like so much fun!
This will ship free with Amazon Prime or qualifies for free Super Saver Shipping with a $35 purchase.
Note: Amazon prices and promotions can change at any time. The price(s) listed in this post is/are subject to change.