Dark energy makes up nearly 75% of the total energy budget of the universe and is the agent responsible for the observed accelerated expansion of the universe. This is a polite way of quantifying how very little we actually know about what makes up the universe and what is causing it to expand ever faster. Despite the spectacular improvements in observational cosmology to date - pinning down the detailed nature of dark energy is notoriously difficult with cosmological surveys alone. In this talk we will discuss the dark energy problem and its possible solutions. In particular we will focus on an exciting proposal - chameleon dark energy - and the possibility that we can learn about the large scale features of our universe within the fairly small scale setting of the laboratory - in fact at Fermilab itself.