Well bitcoin has been around for seven years to my knowledge and is nothing new, but the major problem with it has generally been the lack of stability - the value fluctuates so wildly that what you spend fifty quid on on Monday could be worth ?200 on Wednesday and then 27p on Friday, if you get the idea.
I have no idea whether that aspect has improved, although I would imagine it has since it can't have got any worse. Bitcoin has indeed been used to pay for illegal items on the internet including drugs, but to say it was 'invented' for this purpose is a bit like saying banknotes were invented so that people could buy drugs with them in pub toilets, just because sometimes they do. It's a peer to peer electronic payment system, that's all.
If anybody's tried bitcoin with Backpage I'd be interested to hear about it, and not just because it'll get the thread back on topic

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