Wolfgang's Vault, the business built around the Bill Graham archives, has recently started streaming 300 of the promoter's classic concerts. The Who, CSN&Y, Black Sabbath, Grateful Dead -- there's a ton of stuff to check out. Login required.
How'd these gems get unlocked? They were acquired in a mass purchase of Bill Graham's archives for ~$6 million by a former health care executive. The artwork was his main focus but once the quality and depth of the music recordings were understood, it became clear that there was an opportunity here. And it's one of those weird situations where releasing them for free is actually easier than paid downloads or pressing cds (due to the negotiations those would require). For now they're all online and being used to cross-sell the collectibles offered on Wolfgang's Vault.