Who better than Bruno Mars to lead the promotional blitz for Twilight's latest soundtrack? Mars' clean-cut looks and gently scuffed croon make him an ideal nonthreatening crush – and last year's smash "Grenade," on which he threatened to blow himself up for attention, proved his knack for overheated romantic dialogue. Mars gets similarly melodramatic on this ballad ("If you ever leave me, baby, leave some morphine at my door"), but the real point is the song's desperately yearning melody. It sounds a little bit like "Wild Horses," and a lot like Mars' next radio juggernaut.

Listen to "It Will Rain":

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“Everyday People”

"Everyday People" managed to trailblaze in two different ways -- it was one of the first pop hits to deal with the subject of racial harmony, and it utilized Larry Graham's "slap" technique on the bass guitar, which would soon be copied by countless other bassists. Graham once said about his pulsating style, "I'd never done that before … that's where the freedom of creativity came in for the band, that we'd be allowed to do that." In 1978, the song's line "Different strokes for different folks" would be borrowed for the title of the hit television show Diff'rent Strokes.