Click to listen to selections from Alligator Records: 40th Anniversary Collection

Still thriving, still independent, this Chicago label still serves only Genuine Houserockin' Music, as it said in ads for guitarist Hound Dog Taylor's 1971 debut, Alligator's first release. Founder Bruce Iglauer has always gone deep and wide within that definition. So the icons and belters on this two-CD party include guitar lords like Albert Collins, Son Seals and Luther Allison; vocal volcanoes Koko Taylor and the Holmes Brothers; and the modern-Delta stylist Corey Harris. A track from Professor Longhair's last date is here, as is the guitar dream team of Lonnie Mack and Stevie Ray Vaughan — proof of a catalog worth further jubilant study.

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“My President”

Young Jeezy teams up with Nas on this track, in which he compare his own success with the idea of an African-American winning the Democratic Party's nomination in the 2008 presidential election. "When I pulled up in my car, that s--- was unbelievable to people in my neighborhood because they were like, 'We grew up with him. How the hell did he accomplish this?'" he told Rolling Stone. "I feel like it was the same way with Obama. I grew up all this time, but I've never seen a black man this close to running this country."