Credentials: Tha Carter III, Dedication 3, four Top 20 singles off Tha Carter, "Love in This Club Part II," "My Life," "Can't Believe It," "Swagga Like Us," "Turnin' Me On" 

Lil Wayne's commercial, creative and cultural ascent reached its peak in 2008, the year he became a true crossover star and, without question, the greatest rapper alive. It had been two years since his last album, but Weezy had flooded the industry, releasing a succession of hot street tapes and guest verses. 

First, his guest verses: Lil Wayne was a scene-stealing rap star, making his mark on T.I.'s "Swagga Like Us," T-Pain's "Can't Believe It" (platinum) and Akon's "I'm So Paid" (platinum). He also made his mark on R&B, turning up on Keri Hilson's "Turnin' Me On," Lloyd's "Girls Around the World" and Usher's "Love in This Club II."

But it was his work as a solo artist that made the biggest mark. Wayne managed to drop one of the best 12 inches in history with "A Milli"/"Lollipop." The street single, "A Milli," was a triumph of production ingenuity and lyrical invention; it reached No. 6 on the Hot 100. His radio single, the Static Major–assisted "Lollipop," topped the pop charts, went five times platinum, and helped drive Carter III to 2.88 million in sales by the end of 2008, during one of the worst climates for selling records in industry history. Two other singles were released from this record; "Got Money" with T-Pain hit No. 10 and sold double platinum, while the platinum-selling "Mrs. Officer" reached No. 16.

By this point Weezy's claim to be the greatest living rapper on Tha Carter II no longer seemed nearly so audacious. Tha Carter III was released in June 2008, three years after his last LP. Despite taking a "break" from official releases, his album went three times platinum, opening at No. 1 on Billboard and selling more than 1 million copies in its first week. It became the rapper's best-selling album to that point. It was the first to reach 1 million in sales since The Massacre.

As impressive as the numbers were, though, what made Lil Wayne the greatest rapper alive in 2008 transcended popularity. He had broadened what was thought possible for a rapper. The boundaries of the genre were pushed to their logical breaking point. He was still rapping, retaining his innate cleverness and style, but had such intoxicated confidence that he didn't need to live by the formal limitations adhered to by lesser MCs.

And then, not content to rest on his laurels, he released Dedication 3, another mixtape with DJ Drama, before the year let out. 

Honorable Mentions: T.I., Young Jeezy, Kanye West
Wayne's competition in 2008, while strong, wasn't coming close. Despite the relative flop of T.I. vs. T.I.P. the previous year (not to mention his legal travails), Tip picked up where he left off with King and stepped up his pop appeal. "Whatever You Like" became T.I.'s first No. 1 single that year, surpassing "What You Know," which peaked at No. 3 in 2006. The album, Paper Trail, included two more major singles (including another No. 1 in "Live Your Life.") 

Young Jeezy, in the meantime, released his strongest record since Let's Get It: Thug Motivation 101 with The Recession. It was his second No. 1 LP. He also appeared on Usher's "Love in This Club," which would also find the top spot. He didn't regain the widespread commercial appeal that he had on his debut record, but the album was a creative success, particularly after the disappointment of 2006's The Inspiration.

Kanye West had a fairly low-key year in 2008, but in the wake of Graduation's 2007 release, he remained one of hip-hop's biggest stars. His final single from Graduation, "Homecoming," was released, and he began working on his tortured melodic album 808s and Heartbreak. But as a rapper, he kept the flame alive with a series of hugely popular guest verses, appearing on Estelle's "American Boy," Young Jeezy's "Put On" and T.I.'s "Swagga Like Us." — David Drake (@somanyshrimp)

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