Thinking Outside of the Box

I am pretty broke... Well I guess most people struggle after grad school so I am not alone. I am trying to find creative ways to get in extra strength and conditioning outside of practice. Work keeps me super busy with the two and a half hour total commute and the fact that teaching is a job one takes home. I also do not have the money to join a fitness gym. Yesterday I ran all the way to the pet store and then back with a 40 lb bag of dog food. I am looking to find practical, inexpensive and quick ways to get in small strength and conditioning work outs! Suggestions are welcome! Any ideas out there?