I'd like to call your attention to the quaint game of Line Rider. A simple online game in which one draws lines for a little guy on a sled to follow.
Well... not so simple. There are three kinds of lines. Those on which the sled just slides, those on which the sled accelerates or decelerates. and those which are just there for decoration. Skilled people spend hours getting all the little line segments lined up so that the little sled does all sorts of amazing tricks. To get a sense of what can be accomplished watch Millenium by DaPoe, Transcendental by TechDawg, or Line Rider Die at the Slopes by D4N3Train. If you want some idea of how the tracks are put together watch a short tutorial on track making.
If that doesn't blow your mind then may I present The Line Rider Community Collaboration's Evolution of Line Rider. Give people a creative tools and it's amazing what they'll come up with.
And while I don't have the time, energy, patience, or ability to make Line Rider do amazing tricks and stunts (nor the creative ability to fill in interesting backgrounds) I'm very glad that some people do. And that those people get to share with the rest of us.