During our daily walks we'll sometimes clean up trash on the roadside. Usually it's the same old crap: fast food containers, soda containers, beer bottles & cans (for a while there was a string of extra large cans, all flavors, like a drinking and driving sampler), and empty cigarette packs.
On the rare occasion something unique shows up. Twice now I've found cast off CDs. You'd think that after being tossed out the window of a speeding car and a few days in a ditch they'd be beyond redemption. The first CD was a dinged up but playable Van Halen classic. The latest one is homemade and, despite having this nice sized cigarette burn, still mostly playable. I have no idea who or what it is. A cross between Korn and Rage Against the Machine (the KRAMberries?). Have I discovered a burgeoning garage band demo disk? Of course it could be any of a hundred new groups I haven't heard of. No help from the CDDB database. Is there an app which can derive a unique music fingerprint and id it?