Here are some unusual recordings.  They were made this past Monday evening during my Music Philosophy and Aesthetics class.  We divided the class into three groups, each singing a separate part.  Each group sang the same line, repeated over and over again, but the first group sang the syllables one beat long, the second two beats long, and the third three.  Thus, they start together but the parts separate more and more as time goes by.  The harmonies are just whatever happens to happen.

Then I ran it through a reverb program that makes it sound like it was in this medieval church in Italy.  Give a listen: