Every once in a while, we find it's important to stop and recognize passion when it is literally screaming in our face and won't stop—that's what we did last year when we came across one enthusiastic straphanger who loves to shout-sing Michael Jackson's "Thriller" for his fellow underground travelers. Except it turns out that everyone loves jamming out to "Thriller," and/or watching others do so. Like this gentleman who let loose at Times Square this week.

What is this song that inspires (at least three) folks to throw off the shackles of civility and sing an ode to the beast about to strike?

What is this song that can inspire disparate groups of people to unite in service of a higher, semi-coordinated calling?

What is this song that causes even the most hardened violinists to shred?