"Earth" by Imogen Heap

I’ve been a fan of Imogen Heap for several years. Her latest album Ellipse has one of my all time favorite songs—Earth [listen]. It describes how a frustrated Mother Earth deals with her rambunctious offspring, homo sapiens. [lyrics]

…
These Legoland empires choking out mine
Now you’re everywhere, everywhere multiplying around me child
A strain on my heart
This rock can’t tolerate anymore

[Chorus] Stop this right away
Put that down and clean this mess up
End of conversation
Put your back in it and make it up to me now…

Earth is a polyrhythmic, polyphonic, a cappella masterpiece.

Her breakthrough hit may have been 2005's Hide and Seek [listen], which features her processed voice with minimal accompaniment. It was covered beautifully [listen] by the UCLA 'Awaken' A Capella group.