Do you have a goal? Or are you just running because it's awesome?
Try running the route faster. (duh

)Or the other direction to hit hills differently. Run it faster. (Did I already say that?

) Run it twice. Break it into intervals. Run it as a fartlek.
There are tons of ways to change things up. I'll never understand why some people say running is boring.
I'll think of more. I'm headed out the door to a race.