A, B, and C are almost certainly different addresses in the same wallet, and belong to one person. But in case you're wondering, clicking "Show scripts & coinbase" in blockchain.info will show you exactly how much came from each address.

No, this has always been around. In fact, it's pretty rare to find a transaction that doesn't send to two or more addresses, since transactions usually have to make change.

Both of these situations are explained in Chapter 9 of the whitepaper. Note that there's actually no limit on the number of outputs, and although a transaction from one person to another will normally only have two outputs, it is possible to use more than two outputs, for example when sending to multiple people with one transaction. The whitepaper only provides examples of the most common situation.

"Pray that there's intelligent life somewhere up in space,
'cause there's bugger all down here on Earth." -- The Galaxy Song

This may be a stupid question, but did you have "Hide extensions for known file types" in Explorer turned on when you created your bitcoin.conf file? If so, you've probably accidentally named your file "bitcoin.conf.txt" - that won't work at all. This "feature" is probably the single most annoying thing I've ever had to deal with on Windows systems - and that's saying a lot. Turn it off and leave it off, and your life will be a whole lot less annoying.

What Gabi said. The (out of sync) warning was introduced after a huge number of people complained that Bitcoin-Qt wasn't working properly, when really the problem was that they were trying to use it before it had finished synchronising with the network.

Please use the latest version of Bitcoin-Qt and leave it open until it has finished synchronising (which will take several hours or maybe even a day or two depending on your computer - it has to download and verify the entire transaction history; fortunately you only have to do this once, after that it only has to download new transactions to keep up to date). Don't try to do anything with it (except encrypt your wallet and back it up, in that order) until it has finished (however, you can shut it down and then restart it later if it's taking too long - it'll pick up where exactly it left off rather than starting from scratch, so you don't have to download it all at once if this is not practical for you).

Just shut down Bitcoin, download the latest version, and install it. Back up your wallet first in case things go wrong (really, you should back up your wallet anyway whether you're upgrading or not), though usually nothing goes wrong. Your old wallet and blockchain will not be touched during the installation process and will be recognised and updated automatically when you start the new version.

Whether 'tis nobler in the mind to suffer
The harsh restrictions of the outrageous noob jail,
Or to create meaningful content against a sea of spam,
And by posting, end them?

I have spiders in my room. All insect problems solved.

I don't get it. If I pay $50 for a box containing $40, and you get paid $30 to put $20 in a box, how is that any different from me just giving you $10? Are people really stupid enough to not realise that? Oh, wait, I just got it.

It's the average share price over the last n days. It's used to even out day-to-day fluctuations to get a better general idea of the price.

I kid you not. If you want to collect rainwater for any purpose in Colorado, you have to pay an exorbitant fee for a special permit (which can be refused for any reason and is subject to arbitrary restrictions) in order to essentially buy your rain from the government.

Probably either a figment of some tinfoil-hatter's imagination, or radiation from the van Allen belts interfering with the camera. (To anyone who suggests that this radiation would have been fatal and this proves we never went to the Moon, the radiation levels were already determined to be non-fatal before manned missions were planned, and in any case, over 90% of the Apollo astronauts who left Earth orbit later developed a specific form of cataracts caused by radiation poisoning, proving that they were exposed to an unusually large dose of radiation, such as would be caused by travelling through the van Allen belts.)

HAARP refers to the High Frequency Active Auroral Research Program, which has been blamed by tinfoil-hatters for all sorts of things including earthquakes, floods, storms, drowsiness, and lack of appetite, despite being just a big HF radio transmitter with some fancy sensors to measure changing ionospheric conditions and how radio waves are affected by them. Since this is boring to most people, and most people assume that such a huge project ought to have a correspondingly exciting purpose, they tend to believe that the whole thing is just a cover-up for something nefarious, when really it's just a boring experiment studying boring radio waves. It's important and useful research for radio astronomers and people developing long-range RADAR equipment and the like, but that's just not exciting enough for most people.

How's this for Moon conspiracy: apparently, Buzz Aldrin was supposed to be the first man on the Moon, but Neil Armstrong decided that since he was in command, that honour ought to belong to him. Aldrin went along with it, presumably because low-gravity boxing techniques had yet to be developed, but got his revenge by refusing to take any photographs of Armstrong. If you've ever wondered why there are no pictures of Neil Armstrong on the Moon other than the fuzzy images recorded by the lunar module's TV camera, now you know.

Nonsense. Transporter operators have much higher ethical standards than that. Nobody vaporised the duplicate Riker created by accident when a second transporter beam was activated when the first one became dangerously unstable, then the transporter operator forgot to deactivate the first beam, causing the poor guy to be rematerialised twice. Both Rikers were allowed to go on with their lives, though no record is made of society's reaction to the news that transporter operators can duplicate people just by pressing a button. (Probably because, due to the aforementioned ethical standards, transporter operators would never duplicate people deliberately. Oh, no. That absolutely never happens, right? Right?)

Actually, you can ditch BitPay right now and stop paying their fees simply by setting up the Bitcoin software on your server yourself, securing the server yourself, integrate it with your website yourself, and doing all that other complicated stuff all by yourself. Since doing all this yourself is not very easy, and not even advisable if you have no experience in these areas, you pay other companies to do it for you. You probably pay for water too, even though you could, if you wanted to, install a rainwater tank to collect your own water and pump it and filter it yourself for free*. It all comes down to convenience vs. cost. BitPay makes handling bitcoin payments far more convenient than managing it all yourself, so it's only fair that they receive a fee for their services. It is most unlikely that anyone will offer similar services for free, since there are real costs to providing these services.

*Except in Colorado, where the rain is government property and preventing it from going down the drain is considered stealing. Technically, you can be arrested for staring at the sky with your mouth open on a rainy day.

Other forums don't usually use HTTPS. It's possible that your browser is configured to block images from non-HTTPS sites when using HTTPS. Do you get an "insecure content" warning when viewing threads containing images?

Erm, no, you can store an infinte number of rational numbers. Representing the set of all real numbers (both rational and irrational) is harder, and may pose a potential security risk for the infinite divisibility fork: creation of infinite bitcoins through an infinite overflow caused by sending an irrational number of bitcoins (proving that bounds checking is still important, even when dealing with infinite memory).

It was a joke. People are constantly claiming that bitcoins are "infinitely" divisibile, which is of course completely ridiculous. And an "arbitrary" range is equally ridiculous if it is taken to mean "anything up to infinity", I was just pointing that out by taking that statement to it's logical extreme. I wasn't really expecting my comment to derail the whole thread. Oh well.

Actually, no computer can, not even one with infinite memory, since an infinite amount of memory can only represent a countably infinite range of values, while the range of real numbers (not integers) is uncountably infinite. Fortunately, it is possible to infinitely divide an infinite range of integers without using non-integers for infinite future expansion (see Hilbert's paradox of the Grand Hotel for details), so this isn't an issue for Bitcoin. Though it's a moot point anyway since no computer in a finite universe can possibly have an infinite amount of memory in the first place, so bitcoins won't really be "infinitely" divisible until we extend the protocol beyond the physical limitations of our universe (this will require a hard fork).

With Bitcoin, you can securely transfer money to anyone, anywhere in the world, anytime, day or night, even on weekends and holidays, have the funds "clear" in about 10 minutes on average, and all this for less than a penny in fees. No other means of transferring money even comes close.

Depends on what you mean by "large". Anything under $100,000 worth shouldn't be too difficult. Much larger amounts than that are possible, but not as easy and certainly not advisable, as bitcoin's market cap is only around $100,000,000 at the moment, so it only takes few million dollars or so to seriously disrupt the market.

Why, yes, I am tried some "unusual blends" of "herbal incense".

As others have said, waiting for more than 1 or 2 confirmations is overkill unless you have reason to suspect your customer will be willing spend millions on an attack which will be immediately obvious after he executes it. Such an attack has never happened before and is very unlikely to be successfully attempted in the future.

In any case, what other electronic payment systems exist that allow you to securely and irreversibly transfer funds anywhere in the world in less than an hour?