The Titanium Spring Loaded Insoles from Hammacher Schlemmer have five titanium springs in each heel.
Built with five titanium springs that not only cushion and support the foot, these insoles return some of the energy of the downward footfall back up to the body for a "push off" with every stride. The titanium construction ensures the springs will never wear down or lose their shock-absorbing capability. Seven smaller springs under the ball of the foot further disperse the impact and cradle the foot.
All this for only $30! Sounds like it's too good to be true doesn't it? Well it is. I felt their marketing spiel clearly implied that these things give you the power to jump over buildings in a single leap. And that didn't happen. Nope, I didn't even make it over the holly bush in front of my parent's house. Talk about some false damn advertising. I'm suing Hammacher Schlemmer for the cost of Neosporin and Band-Aids.