Now in their 20th year of business, Tool has solidified themselves as their generation's go-to prog band. Nothing about the L.A.-formed quartet has ever been run-of-the-mill. From 1992 debut EP Opiate onward, the band set a course that would lead to a cult of massive devotion and eternal mystery among their fans, mostly surrounding lead singer and newly minted winery tycoon Maynard James Keenan. Tool only has four studio albums under their belt, but each has been deconstructed time and again by guitar and drum fetishists, cementing their place as one of the most accomplished metal bands in history. (Three Grammys don't hurt, either.) Given the band's track record of waiting five years or so in between albums, Tool fans are due a follow-up to 2006's 10,000 Days soon...or soon enough.