Best duet ever

I'm sure I've blogged about this before, but I can't find it, so here it goes again...

"Ain't No Mountain High Enough" by Marvin Gaye and Tammi Terrell is, far and away, the best duet ever. Their voices wrap around each other so tightly that you believe every word of it.

The best moment of the song: 1:40 in, when Tammi's line is "My live is alive" and Marvin throws in a falsetto "Woo!" just for the hell of it. Pop music doesn't get any closer to perfection than that.