The cost (in terms of time and energy - hence higher utility bills) is in part where they derive their value. The use of the term "mining" is therefore relatively appropriate, since it too takes time and money. Of course for something to have value requires it to be accepted for payment for goods/services, which is currently a little difficult with Bitcoin, although one would hope that the array of people accepting it does start to increase.

Would certainly agree that it's volatile at the moment, but that's not particularly surprising either. It does seem to be back around $24 now (which strikes me as still probably overvalued).

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