Neodymium
magnets also happen to be of the strongest magnets known to
mankind. And guess what? You happen to be sitting near one right now. The magnets in most
hard drives are neodymium magnets. If you have some old harddrives laying around, don't throw them away! Rather, bust them open and
steal their magnets! You'll be surprised at how
strong they are.
Recently, I did an experiment wherein I got hold of three tubes: one copper, one aluminum, one plastic (the control). I dropped a neodymium magnet down each of the tubes and the results were amazing. The magnet dropped down the copper tube actually fell slower than 9.8m/s2 (the acceleration of gravity). The aluminum also had a slight effect and, of course, the plastic PVC pipe had no affect on the rate of fall. All this was due to Lenz's Law and the strength of the magnet.