If there's a market for Power Crystals there's a market for Baby Einstein tapes. Will they work? Of course not! They don't work on babies it was always just a scam. The whole baby einstein thing started from a SINGLE study on UNI STUDENTS that found that if a student listened to soothing classical music before an exam vs. heavy metal they performed better. That's where it all comes from.
I bought the Baby Einstein dvds after a friend suggested it. If they work or not? I can't say this for sure. But they provide visual and auditory stimuli which can relax and enhance learning, so I guess there's no harm done.