Why rent when you can own?

I don't know about you, but I am bored to death with none of my TV shows on this summer. You can only play Wii so many hours a day before you long for the pithy humor of Corner Gas, the drama of Grey's Anatomy, the delusional queasiness of LOST....
So to fill the hours hubby and I have been watching lots of Redbox movies. They are a great price, just $1.00 per daily rental. However, our machines are a bit picked over right now.
At a yard sale today, I found the DVD Robots, which I haven't seen yet (I know I live in a cave or something). It cost me a whole dollar. I could have rented Redbox today or purchased a movie that I can watch over and over again and eventually resell at my own yard sale. hmmmm. I think there's a financial lesson here somewhere...