I just read an interesting blog post by a Googler named David Wurtz. Summed up, he says that smart people should do stupid stuff. The point is that you don't have to tackle the biggest challenges to be successful; you can find something more down-to-earth and find lots of success working with that instead. A quote:

Although I endorse those  who attempt to spend their time defying gravity (the world needs these people), I simply think students simply forget that the real world is not graded by professors with untamed beards.  Students are largely unaware that they could realize just as much success, or perhaps even more success, if they point their incisive intellect at simpler, "stupider" problems. So why don't they?