When soft rock and rap collide

Some musical genres are natural fodder for hip-hop beats: funk, soul, jazz -- even hard rock.

But light rock? Mixing soft acoustic strains with aggressive 808 beats can be a recipe for disaster -- or genius. When it works, the counterintuitive blend can be tasty -- like ranch dressing on hot wings. Other times, the mixture is more like dipping nacho chips into whipped cream. Just ask Jay-Z.

Hov is no stranger to odd musical pairings and scored a huge hit in 1999 by sampling the musical "Annie" on the song "Hard Knock Life." But he recently faltered when he enlisted the king of wuss rock to supply him with a beat and a hook.

His latest album, released last week, flaunts a track with production and crooning by Coldplay's Chris Martin. "Beach Chair," is slow, a bit dreary and features very un-raplike lyrics from Jigga: "Life is but a beach chair." Huh?

Of course, some FM-meets-AM mash-ups work better. Lord Tariq and Peter Gunz sampled Steely Dan to great effect on their hit "Deja Vu." But Kanye West's recent collaboration with Maroon 5's Adam Levine? Not so much.

Whatever we may think of the aesthetic power of these strange bedfellows, one thing is for sure: the artists involved have a good chance of raking in the cash when they cross-market their music.

In honor of Jay-Z's foray into soft rap, here's a look at what happens when hip-hop and soft-rock collide.

"I'll be missing you" by Puff Daddy and the Family

Scenario: Puffy pillaged not only the Police's classic "Every Breath You Take," but also the memory of Biggie Smalls for a bit of forced sentimentality.

Sellout factor: Off the charts. It's hard to outdo Bad Boy Records' Proactiv-and-Pepsi-pitchman, but Sting managed such a feat by singing the hook with Puffy at the 1997 Video Music Awards. The Police's delicate melody will forever be soiled by Puffy's ham-handed rapping.

Worth it?: No. The Police sample made for an awkward hip-hop beat, and the 1997 song sounds extremely dated nearly a decade later.

"Until the end of time" by Tupac

Scenario: Tupac -- or rather the producer of this posthumous 'Pac hit -- single-handedly funded Mr. Mister's retirement by sampling the band's '80s hit "Broken Wings." Another Shakur smash, "Changes," sampled Bruce Hornsby's "That's Just the Way it Is."

Sellout Factor: This 2001 track is a no-fault collabo. Tupac was already dead, and how else was Mr. Mister going to keep those royalty checks coming? "Broken Wings: Encore Collection" ain't exactly flying off the shelves.

Worth it?: Yeah! "Broken Wings"' ethereal synths pair well with the rapper's majestic flow, and fit like a glove with a heavier hip hop beat and the obligatory church bells of Tupac's later work.

"Heard 'em say" by Kanye West

Scenario: The rapper-producer extraordinaire dialed up Maroon 5's Adam Levine to add falsettos to the chorus of this mid-tempo 2005 release.

Sellout factor: Negligible. For West, not nearly as foolish as casting Pam Anderson in a video. And it made Levine appear more soulful.

Worth it?: Not really. Levine's squeal is positively superfluous. The song -- which boasts a slinky, tinkly beat and West's mellifluous flow -- would have sounded better if Kanye had sung the hook himself.

"Stan" by Eminem

Scenario: Slim Shady jacked the hook from Dido's "Thank You," snipping the chorus in half right before it got to the uplifting part.

Sellout factor: Minuscule. The track gave the up-and-coming Dido extra exposure and didn't meddle too much with the sound she created.

Worth it?: Absolutely. Dido's contributions imbue poignancy into this 2000 song that could have otherwise drowned in its macabre, graphic content. Many of Slim Shady's other morbid raps have come off sounding bizarre or even a tad silly.

"Deja vu" by Lord Tariq and Peter Gunz

Scenario: This one-hit wonder pulled Steely Dan's "Black Cow" from the soft-rock dustbin for a 1997 smash that inspired countless remixes and had fans chanting "Uptown baby!"

Sellout factor: Small. It's not clear whether the rap duo actually had permission to use the sample, and the rappers eventually ceded all royalties to Dan's Walter Becker and Donald Fagen. "We don't make a dime off the song," Lord Tariq told Rolling Stone.

Worth it?: Most definitely. The jazz-rockers' spaced-out bass line was tailor-made for dropping into a hip-hop song. In fact, the resulting rap track sounds terrific with little adornment beyond looping "Black Cow's" initial break.

"Sometimes I rhyme slow" by Nice & Smooth

Scenario: In 1991, Greg Nice and Smooth B. pointed a hyperactive drum machine toward Tracy Chapman's wistful "Fast Car" riff.

Sellout factor: Medium. But hey, we can forgive Chapman for cashing some royalty checks during the lean years between '88s "Fast Car" and '95s "Give Me One Reason."

Worth it?: Greg Nice had us at "sweeter and thicker than a Chick-O-Stick." It's hard not to smile at this infectious yet somber track. When that familiar acoustic riff comes on in a bar, it's hard to say which song would be better to hear.

"Stan" by Eminem

Scenario: Slim Shady jacked the hook from Dido's "Thank You," snipping the chorus in half right before it got to the uplifting part.

Sellout factor: Minuscule. The track gave the up-and-coming Dido extra exposure and didn't meddle too much with the sound she created.

Worth it?: Absolutely. Dido's contributions imbue poignancy into this 2000 song that could have otherwise drowned in its macabre, graphic content. Many of Slim Shady's other morbid raps have come off sounding bizarre or even a tad silly.The