bitcoin mining vs password cracking?

[Tasselhoff]

The Bitcoin exchange rate is completely unstable due to speculations. As long as that problem is not solved, no economic success willl occur.

Besides Bitcoin mining is one huge waste of energy, converting precious electricity into virtual whatever.

Agreed about the waste of energy. And if you're going to do it, get an ASIC which will be far more efficient than a GPU https://www.buybitcoinworldwide.com/mining/hardware/