If you type in "pikachu curve" or other famous fictional characters on wolfram alpha it generates a function to trace out the curve that resembles the character. See http://www.wolframalpha.com/input/?i=pikachu+curve .
Does anyone know how these curves are generated? It seems that this has been done for several characters so I doubt that they worked out the details by hand.
Related: Is this Batman equation for real?
Visit Wolfram's blog. It has many nice applications of Mathematica.