Time to dust off that old physics degree and put it to use. If I can teach first graders how electricity works (it's a bunch of chickens leaving a crowded coop for a more spacious one), surely I can help @vinny and @danryckert get their quant on using that ever-helpful example, beer.
1) The hell does "quantum" mean? The word itself comes from the the root "quant" which means "count" and the discovery that energy actually exists in countable amounts, and that there is a smallest unit of energy. It was previously believed that a particle's energy could be WHATEVER. Nope. You can have 1 energy, 2 energy, 3 energy, etc. the same way you can have 1 beer, 2 beers, 3 beers, etc*
2) What's with Schrodinger's cat? A curious fact of quantum physics is that it presents a view of the physical world which deals in PROBABILITY. That is, it becomes impossible to say "my beer is right there on the coaster." We instead have to say "my beer has a probability of being a lot of places, but the chance that it is on the coaster is ASTRONOMICALLY HIGH compared to everywhere else." This seems ridiculous, right? That's the whole point of the Schrodinger's cat thought experiment -- that quantum phenomenon, which seem pretty rock-solid when looking at tiny particles, seem completely absurd when applied to human scale.
Without getting too deep into it, let me just say that this probability business is derived from the fact that things are typically not in a single state, but are rather in multiple states at the same time, but in different amounts. We say that an object is in a "superposition" (layering, or combination) of states. The math says that the beer is both ON and OFF the coaster -- it's just a matter of amplitude.
3) So, how does that answer the cat thing? OK, so you put a cat in box. You also throw in one of those roach-killing bug bombs and hook it up a trigger contraption. At the risk of oversimplifying this, let's say that the trigger contraption essentially places an electron (that's a small particle) at a fork in the road. If the electron goes left, it activates the bug bomb and the cat dies. If the electron goes right, the bug bomb breaks and the cat lives. You then seal the box up and throw it in the closet. Is the cat alive or dead? Well, you see, the electron went both left AND right. It is in a superposition of both states. The cat is thus in a superposition of states as well: it is both dead and alive. I'm not even going to get into the "observer effect" part of this, since there's plenty of bad pop science out there on that already (and having written in college a pretty bad paper about the Copenhagen Interpretation of the Heisenberg Uncertainty Principle, I should probably sit out any talk involving the collapse of wave functions).
The thing to keep in mind though is not that this would actually happen - that cat in the box is either dead or alive - but that the things which seem true for tiny little particles seem NUTSO when extrapolated out into human scale. The Schrodinger's Cat business is a mixed bag (or a "superposition of bag states"). For every layperson out there who hears about it and says "wowza, I want to learn some proper physics" there's probably another who says "this sound like stupid magic, I'm out."
I'm seeing a lot of love in the comments for the Double-Slit Experiment, and THAT is something I can super get behind. A clear example of quantum phenomenon (wave nature of photons) messing with your everyday human expectations.
*The opposite of being "quantized" or countable is being "continuous." An ocean of beer is continuous -- it can rise or fall to any level, but Bottles of beer (assuming you can't drink half a beer) are quantized -- you can only have certain amounts, like 1, 2, 3, ...
Games received as gifts help create that unique game landscape for folks. I probably never would have bought The Neverhood for myself, and I know it's got a lot of major problems, but I received it as a gift when I was kid, so it was The Game I Played until something else came along. Who else grew up playing that and Tony La Russa Baseball 2 and Hoyle Card Games and Civilization 2? Gifts given by people who had never played a PC game in their life, and as such exposed me to games of all types of genres and quality. And someone else received different gifts from different folks with no clue and has their own patchwork game history, and that's just so rad to me.
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