A small news story rolled in back in March about a global shortage of 
*high-end graphics cards. Fabrication problems at a *chip manufacturer? 
Pre-emptive upgrading before the release of *Portal 2? 
Fantastic new developments in the *potato industry? Not really.
Cards were being snapped up by *eager BitCoin miners. 

*BitCoin is a peer-to-peer virtual crypto-currency invented in 2009 by
*Satoshi Nakamoto, a guy who has since mysteriously vanished. But don't let 
that discourage you like a *room full of deadly lasers. 
BitCoin is open source and being actively developed by people around the 
world.

I won't say too much now about the basics of BitCoin, such as how BitCoins
are like *cash and not like a *bank account, how the network guards against
double spending, transaction reversal, and *inflation instead of central 
authorities such as banks and governments. 
Nor will I tell you *where to get BitCoins for free.

However, here are a few *facts. One year ago, one BitCoin was worth 
roughly 6 cents. Today, despite recent volatility, it is worth about $6. 
*Speculating has been very profitable for some.

Instead of simply buying BitCoins, it is also possible to *mine them.
*Mining is a computational process that performs useful work in maintaining
the BitCoin system, namely, BitCoin transactions become validated
and stored permanently as part of *mining. 
For every block *mined, 50 BTC, worth roughly $300, are given to the 
successful *miners of that block. The algorithm also readjusts
periodically to ensure, on average, only one block is successfully *mined 
once every 10 minutes. The more *miners there are, the harder it becomes to 
*mine.

In the BitCoin client app, there is a *CPU-based mining program that
on, say, a *shiny new iMac, mines at about 4Mhash/sec. At the current
difficulty this would expect to mine one block roughly once every *forever.
But since the mining algorithm is essentially *SHA256,
a GPGPU approach is far more efficient. 
A single *Radeon 5970 can mine up to 800 Mhash/sec, and 
therefore about 1 block every week at the current difficulty, 
or 200 times more time-efficient than *some loser with a fast CPU.
Thus there is a great incentive for people to buy and use *mining rigs: 
computers with lots of high-powered graphics hardware. Even taking *power
consumption into account, mining is quite profitable. Plus, you get to *keep
the hardware in case everything goes south.

Of course, all this may be moot in the next 18 months, as 
authorities across the world start banning BitCoin like *anything else 
they don't understand. *Thankyou.