polyp2000 writes: A pair of Spanish engineers have recently unveiled the dAlH2Orean (see what they did there?), a R/C car that runs on aluminum. Dropping a few soda can tabs into a tank of sodium hydroxide produces enough hydrogen to power the little speedster for 40 minutes – at almost 20mph. Link to Original Source
We warn the reader in advance that the proof presented here depends on a
clever but highly unmotivated trick.
-- Howard Anton, "Elementary Linear Algebra"