Sammy Hagar is just a couple of weeks away from his 70th birthday, but you'd hardly know it.The man known at the Red Rocker continues to work at a pace near what he did when he emerged as the frontman of Montrose in 1973. Since then he's led other bands (Van Halen and Chickenfoot), maintained an active solo career and triumphed as a businessman with his Cabo Wabo Cantinas and tequila and rum lines -- and, most recently, Santo Mezquila in partnership with Maroon5/"The Voice" star Adam Levine.