Due to the heavy competition, mining BTC on a standard machine is no longer worth it. Unless you have access to "free" electricity, you're better off buying one.

Consumer-grade mining is a temporary phenomena. In a few months, the block reward will be dropping in half, and most people with GPUs will no longer be able to operate them profitably for mining. This is because FPGA mining hardware has been shipping in volume.

In addition, if ASIC hardware starts shipping, GPU is completely out of the game and FPGAs will be hard pressed to stay powered on.

GPU mining had a good run for nearly two years, but it is about to be obsoleted.

So, the only way to get some bitcoins for a single person would be hacking sites like bitcoinica or users? Also, is there a live statistic, which shows how much bitcoins exists right now?

Hacking?

You can buy them, you know. That's the whole point of Bitcoin exchanges.

Maybe he likes to pay the iron price.

Your hardware is too bad if you don't have a dedicated miner with specialized hardware.

hmm so who own the best hardware win the game? what if Google decided to join!?

A company like Google could probably hijack the bitcoin network. However, no matter how much hardware you throw at it, you will never make more than 300 BTC per hour. So it would be unlikely to be economically feasible to throw a giant server farm behind calculating bitcoins.

Perhaps it would become a sensible concern if a country would adopt BTC as their currency and another country would decide to attack that country by destroying their currency.

I think I might be inorrect: if somebody hijacks the bitcoin network, perhaps they could make more money by changing transactions of the past. Not really sure, though. Anyway - that would only destroy the network, not really make them richer.

It amazes me that the initial bitcoin set up was basically a pyramid scheme and this doesn't seem to put anyone off.

Not to mention the fact that all that computing work is wasted doing nothing useful.

I'd much rather see grid computing networks offer signed certificates proving that you did a certain amount of work for them in place of money, but also allow you to swap them for cash.

That way, the computing power did something useful. Sure every grid computing network would be it's own 'central authority', but as long as they all adhere to a common api, I don't think that's a problem.

The computing work secures the block chain. That's the opposite of wasted.

In your computation certificate proposal, would you be able to trade certificates? If so, each grid network would be able to trade counterfeited certs (generate certs for which no work was performed). If not, it isn't a currency. Not to mention that exponential increases in computing power would cause the system to be inflationary, where a goal of bitcoin is to be deflationary.

> In your computation certificate proposal, would you be able to trade certificates? If so, each grid network would be able to trade counterfeited certs (generate certs for which no work was performed).

Yes, you'd be able to trade certificates and portions of certificates. The point is that the certificates have some real value too since they are essentially vouchers for more computer time on the grid network (some percentage of the time you contributed in the first place), that's why a grid provider wouldn't want to distribute more certificates than necessary.

There are a number of ways around the inflationary problem, the simplest would be for the certificates to be in whole grid computing seconds, so as the grid grew larger and more able, the certificates would increase in value at the same rate.

By the way being deflationary is a really bad idea - it stops investment and shrinks the whole pie of economic activity. Perhaps it wouldn't matter too much for a parallel currency, but for your main currency it'd result in massive unemployment.