After reading this article from Gizmodo, I got my hands on the same FLAC version of Sgt Pepper's Lonely Hearts Club Band. It's pretty shocking how much better the album sounds. It's amazing how much better the album sounds (different instruments in the mix, better drum sound, etc.). Very cool.
http://i.gizmodo.com/5216258/sorry-stereo-but-beatles-in-mono-rocks-a-lot-more