You want to have fun while running?

Go to video.google.com and search for "Parkour".
Parkour is the sport of "Free-running", that is, treating an urban environment like an obstacle course and creatively, quickly, and smoothly running through it.
Really its just jumping over a bunch of stuff.
BUT... the point I'm trying to make is that you can have fun running and get to the point where it is no longer a killer for you.