[Tichy]

I did it for fun two years ago and made a plus.

Since the future price of Bitcoin is unknown, at the end of the day you can not really decide if mining is profitable with maths.

I stopped mining when I generated less money than I spent for electricity (the gear had already been paid off). However, back then the exchange rate was maybe 5$. If I had known that it would be 100$ two years later, perhaps I could have mined longer.

[caf]

Even if you'd known that the exchange rate would eventually rise to $100, once the cost of electricity exceeded the current market price of the bitcoins produced the rational thing to do would have been to turn off the rig and use the money to buy bitcoins on the open market instead of mining them.

[Tichy]

True, I just thought of that and came back here to add that :-)

What the Bitcoin experiment taught me is that I am not a very good investor... The good part of mining was that I did it for fun, so there wasn't much to lose. The mining rig is now my new gaming computer. So even if I hadn't made any money at all, at least I would have gained a new gaming rig. In that sense it was a good speculation, for me personally (no real downsides but potential upsides).

I felt that by mining I also supported the idea of BitCoin, so it had ideological value for me, too.