Increase the Fun Factor

This is great - except in real-life no one gives a crap if you are having fun or not.  So it is up to you.  I personally always take the stairs - I tend to kind of fancy-prance my way up and down.  Like hop scotch.  Or see how many you can skip at a time - that's hard.  For bonus rounds try a slinky on an escalator.  Not really a fitness thing, just mostly annoys those people riding up on it.  I am easilly amused what can I say.