The one where they use a marker on the disc actually got me curious. I mean, people do use that tweak to defeat copy protection, so I conceded the remote possibility that it might help in some other area. But yeah, I sorta figured it was all nonsense. The most I've ever done is to clean a disc with some sort of specially made spray -- the typical disc cleaning fluid. It didn't seem to change the sound quality in any way. The fluorescent light and coloured paper seemed especially silly.
Sometimes I feel bad about those rich guys who actually buy these Shakti Stones and the like; then I feel ridiculous for feeling bad about rich guys, let alone rich guys who are senseless enough to buy these things.
cheers,
supervij