I'd bet you never would have thought that your electric bill could be lowered using hula hoops! It can, if you have a pool. With a little help from Make (via Lifehacker) you can use Do-It-Yourself Hula Hoop Lily Pads to warm your pool and cut a huge chunk off of your electric bill. I'd also be willing to bet that this same hack can be applied to your pond, with enough ingenuity. Below is a video instructional that tells you everything you need in order to create Hula Hoop Lily pads..enjoy!
Weekend Project: Lily Pad Pool Warmers [Make]
Weekend Project: Lily Pad Pool Warmers [Make]