Analogous effects (to those seen in the Schrödinger's Cat experiment)...have some practical use in quantum computing and quantum cryptography. It is possible to send light that is in a superposition of states down a fiber optic cable. Placing a wiretap in the middle of the cable which intercepts and retransmits the transmission will collapse the wavefunction (in the Copenhagen interpretation, "perform an observation") and cause the light to fall into one state or another.(Wikipedia). I seem to have not understood the nature of the Wave Function in this particular case--basically the answer seems to be that Geiger Counter has a wave function representing the decay or lack thereof of a particle (and the life of the cat) that's different than the person outside the box who doesn't know jack about the outcome of the experiment until he opens the box. Such is, apparently, a feature of the Copenhagen Interpretation of reality.
In this interpretation of the universe, the experiment just seems a lot less compelling to me, because the Geiger Counter and the human outside the box will never disagree (that is, the Geiger Counter will never report that the particle decayed while the human later opens box and finds the cat alive). Maybe I'm not seeing the point here, but this seems to reduce quantum weirdness at the macro level to "Stuff that's true that you don't know yet."
I don't know why I'm writing this as a blog entry since, I dunno....something.