Like peanut butter and jelly, like peanut butter and chocolate -- heck, like peanut butter and anything -- sometimes two great (or even not so great) musical forces combine to become more than the sum of their parts. Here are the best examples of duet alchemy.

'Easy Lover'
--Phil Collins and Philip Bailey (1984)

Somehow, 'Easy Lover' weaves shameless cheese into brilliant gold. One reason is the decision by the two Phils to replace the horns they each typically sing over with badass electric guitars. Another is the pair's infectious enthusiasm -- which is odd, as they're singing about a dangerous woman who puts men on their knees. On second thought, their enthusiasm makes perfect sense.