Carbon Dioxide Seperator

I want to create a system to flush carbon dioxide from air. Why? I do have a good reason.
"Stuffiness," the sensation commonly found in enclosed rooms with no air circulation, is almost assuredly a carbon dioxide buildup symptom. The air feels oppressive and stale, and one has an immediate urge to try to open a window. One feels drowsy and irritated, and everything smells bad. I know this because as a small child, I used to like to hide under blankets, which would become stuffy in short order, to the point where I started to associate hot air with stuffy and cold air with fresh. The stuffiness was due to poor air circulation: the carbon dioxide of my breath would build up until I exited the blanket.
NASA probably knows a few ways to do this, as it became critically important on space missions. You only have the air you bring with you in space, so it is critical to keep it as fresh as physically possible. Drowsy, confused, astronauts poisoned by their own breath is a bad thing. Their technique involves a rather complicated membrane system performed under pressure.
If I were to invent my own system, I think I would work with the chemical properties of carbon dioxide itself. I can extract it by cooling it off -- carbon dioxide sublimates long long before oxygen precipitates into a liquid. I can extract it with pressure, bringing the carbon dioxide into its liquid state and siphoning it off. I could even extract it with chemical combinations, like Sodium or Potassium Hydroxide, which tend to absorb carbon dioxide until they reach a saturation point, but I'd want an industrial type technique that I could set up and not have to personally fuss with afterwards.
Having installed one of these systems in a house, stuffiness is banished forever. What to do with the carbon dioxide? I can shunt it out of the house, thus getting all the benefits of opening a window without losing all my heating, which is sweet, but for even better works, I can use it as the security system for a greenhouse. The greenhouse is, when no humans are expected inside, flooded with all the carbon dioxide from the house. All pests die. Any intruder dies. It's just plants and a few bacteria, with the plants slowly reoxygenating the place.

Pneumatic Net

I just read an interesting proposal of adding to, or replacing, the internet with a network of pneumatic tubes to allow it to handle any physical object. This will require some explanation.
Before personal computers were common, large organizations like banks typically had a pneumatic network for exchanging paperwork. One would roll up the relevant paper and put it into a tube, and then put the tube into a slot. A vacuum would then pull this tube to its destination. One could exchange anything that fit into that tube through the network. So while the most common use was paperwork, one could also send keys, a packet of potato chips, or really anything that could be fit into the little canister.
Computers did away with pneumatic networks for the most part because of the difficulty involved. Setting it up was difficult. A preposterously complex network of tubes had to be built in the building, you had to have a dedicated routing room, because the vacuum only went one way, and you had to have really powerful pumps to abruptly suck the air out of any particular tube. So when personal computers became common, most organizations ran screaming from pneumatic systems. After all, the routing room had to sort who got what canister by hand.
I don't see a worldwide pneumatic system coming about without some serious automation of identifying and routing, because the internet has billions of nodes. The routing room, wherever on earth we put it, would have to be a nightmarish maze of pipes with many many OCR readers and supercomputers and robot claws for identifying the tube, putting it in the correct destination, and sending it on its way. No human being could ever hope to keep up. Hence the sheer insanity of this idea.

Spamdomness

Randomness is an interesting thing in computer science, because a computer's numbers are only pseudo-random. Computers are quite deterministic, which makes it quite difficult to produce anything random. And yet, many mathematical techniques depend on reasonably random numbers. What's a programmer to do?
Most existing pseudo-random numbers are based on things that are difficult to detect or determine ahead of time, like a statistical study of keystroke timings, mouse movements, or the thermal entropy in the various capacitors. An "entropy pool" is maintained from the study of numbers like these that accumulates enough to be sufficiently random to, say, produce an encryption key that can't readily be guessed.
When sites want a stronger randomness than that, they often resort to the study of random events outside the computer to maintain an even bigger, and more rigorous random, than can be done inside the computer itself. One common technique is to point a webcam at a television that is tuned to a non-broadcasting channel. The resulting static is effectively random data, which is fed to the entropy pool. One site, Games By Email, has an elaborate machine to throw dice and record their rolls for later use. The site also promises to melt down any die that produces a roll that a customer is not satisfied with, because the customer base tends to strongly anthropomorphize dice and sometimes want to "punish" dice that don't roll the way they want. (And why not, dice are cheap and a satisfied customer is a returning customer.)
This all gave me an idea for a cheap source of pseudo-random numbers: Spam. Spam are unwanted emails that constantly hammer servers and annoy the crap out of millions of people, all because .00001% of people take them seriously and buy stuff because of them, thus handsomely profiting the group that put them out. Most spam is today thrown away, often by automatic means before any human being ever sees it. Or if not, is tossed into a special spam box to be discarded later. Just in case a real message is falsely flagged as spam. Spammers go to elaborate lengths to ensure that the recipient looks at the message.
So, from now on, when a message is flagged as spam, we take a quick hash of it, like an MD5 sum, and then manipulate this into the entropy pool by a pseudo-random means. (Arbitrarily pick one of: Add, subtract, XOR, OR, AND, Replace, Append). This should slightly improve the quality of the entropy pool with every spam you receive. After the summing, the spam can be discarded or added to the spam box or whatever the mail receiving program was going to do with it.
I don't recommend this technique to sites in need of high quality randomness, as it leaves a gaping security hole: An attacker can spam the site with several trillion copies of the same message, thus setting the entropy pool to a known quantity, thus effectively giving the attacker control of the encryption keys. But sites like that probably have a TV static, nuclear decay, or other basically impossible to control source of random numbers in the first place. They also have a lot of money to ensuring the security of their randomness.

Mouse Fountain of Youth

Discovery news says that a group of mice genetically engineered to age rapidly and grow telemerase when exposed to estrogen tend to recover their youth when exposed to estrogen. Already visions of a technological fountain of youth dance in many a journalist's head. Especially because telemerase is something easily obtainable that you could probably inject yourself with as early as tomorrow if you ordered it this morning.
Ah, but not so fast cowboy. The article also points out that this may be a quirk of the rapid aging genes. So maybe it might help someone with a rapid aging condition, but not provide boundless youth to whoever wants it. Even so, this is a remarkable piece of medicine going on here.

Lifting the Low Countries

The low countries of Belgium and the Netherlands, and the Maldives, are quite worried, and justifiably so, about the rising ocean. All three countries are very close to sea level, and parts of the Netherlands were actually reclaimed from the sea at great effort and expense. This post concerns the Netherlands and Belgium the most, as the Maldives can't afford this solution just yet.
I think, starting from the German border, we should carefully record each building's blueprint, demolish it, and rebuild it on poles 60 meters high. We'd also retrofit the plans for things useful to the people, like electricity, phones, central heating and air conditioning, and whatever else could sensibly be installed in the plans, because, well, why not. The streets would be on poles (like a freeway), the houses on poles, with yards on poles. It would be very tall. We'd sweep through the countries doing this until we reached the sea. Then, when the crops are harvested, the dearest plants transplanted, and everyone high and safe, we'd board off the sides and fill the inside with cement to stabilize everything. The low countries would now be the high countries, and would survive the highest sea rise possible.
Expensive, for sure, but I think if national survival were ever on the line, they'd find a way. Also, I think the highness would form a tourist attraction.

Human powered copter

Imagine a device with a little seat, a large propeller, and huge rotors. A small counterotor in the back retains the balance. Sitting in the seat and violently pedaling, the user could lift himself aloft.
...eeeexcept that the rotors would have to be about 30 feet across, and one would have to pedal really really hard. It'd have to be made of the lightest carbon fiber, and even then it probably wouldn't work.

Planar Furniture

I'm imagining a super cheap form of furniture made of boards. Boards in little shapes slapped together to form a chair, and filled with expanding foam in the middle. Or, perhaps just an "X" like shape of more boards. A board chair could be had for $10, and a board bed for $30. Board desks would be maybe $5. For the cost of a professionally made chair, one can buy an entire studio's worth of furnishings. Furnishings that can easily be taken apart and hauled away. Just one problem: They'd be ugly.
True, to make them bearable I'd want to attach lots of cushions, but their primary benefits are also their main detractions. They're going to be boxy, kludge-like in appearance, and tacky. And yet, I believe there is a big market for them with college students (who have to make the most of every cent) and nomads (who can enjoy the benefits of furnishings by being able to take them apart and haul them away.