Sharper Than Ever: A Cappella is YouTube's New Favorite Obsession

By Peter Hoare
Fuse News
January 10, 2014
Prior to Pitch Perfect, there was Indiana University's favorite a capella group - Straight No Chaser. After a decade-old performance of theirs went viral on YouTube, the guys found themselves signed to a major label.
Read more: http://www.fuse.tv/2014/01/fuse-news-rise-of-acappella

There's also a video included with the article.