Eric Whitacre's Virtual Choir performs "Lux Aurumque"

Eric Whitacre... is an American composer of choral, wind and electronic music. He has served as a guest conductor for ensembles throughout Europe, Asia, Australia and the Americas. He is one of the most popular and performed composers of his generation, his works being part of standard choral and symphonic repertoire.  He is inspired by pop and electronic music and is known for his work with virtual choirs—creating choral community via the internet.

Even if you don't like choral music, you should watch a couple minutes of this video to see what can be done with webcams, microphones, and a healthy dollop of imagination.