This is an original by Sam Tsui.
I think it was created for the film Kurt Schneider created for their graduation (from Yale, I'm pretty sure).
http://www.youtube.com/watch?v=n1p74Isbcgc
I love the song... The lyrics are prefectly fit to the melody, and you can hear the way he means what he sings...
And in the music video, he's on a balcony, then he's talking to this girl and they spend time together, and then he helps her pack to go back home after college. Then they load her boxes into her car, and she drives away... then he turns back time and everything goes backwards in fast-forward (or fast-backward...), until he's back on the balcony, where he started. He is holding a watch, which he throws over the end. The song ends, and then the girl comes up from behind him and taps him on the back.
This song is priceless, it doesn't need a rating. :)