Several years ago my friend did that to learn about cryptocurrency. He bought a bunch of GPUs off CL that were being dumped by people in favor of FPGAs (or whatever was the new hotness at the time for bitcoin). He had a bunch of server racks that he got for free when AMEX dumped 'em here locally. Also bought the mobos and ram off CL.

Then ran extension cords from all over his house into his garage to power the things, networked everything together, and played with it for 6 months, mostly over the winter.

He said he was able to break even (that is, mined enough coins - mainly other alt-coins, not bitcoin) to offset his costs in both electricity and what he spent on the hardware. Kept his garage closed and the door to his house open, and it heated things fairly well from what I recall.

In the end, though, he shut it down, because it was starting to go upside-down for him; I don't know what he did with the hardware (he ended up giving me one of the GPUs - so maybe he parted it out for friends to upgrade their systems?)...

What about the time investment? How can you take that into account in an unbiased (or least biased) kind of way?

Well, theoretically he did it because he genuinely wanted to spend that time learning, so the time investment shouldn't be factored in.

Same way that if I go to a movie, I don't typically think about it as costing me the price of a ticket and 2 hours of wages (although technically I could, I guess). I calculate time cost for things that I don't want to do.

If anything I would use the time spent in the value calculation (I payed $13 for 2 hours of entertainment).

There are plenty of movies where I've come out thinking that I'll never get those 2 hours of my life back. I do apply this logic to commute time though. $salary - $commute = $takeHome. Some jobs are not worth it.

I also agree 100% with the time cost on something you're wanting to learn is a sunk cost. After all, it's an investment in yourself. Even if it fails, you now have that experience of what not to do if presented the chance again.

In The Netherlands you get a large part of your travel costs reimbursed by your employer. How large it is, there are legal upper limits to avoid "untaxed extra payment".

If you can travel by public transport, part of the time of your commute is akin to leisure time. But I have big issues with failing to focus, especially if I gotta switch transport multiple times or run to make it or its crowded or...

My limit of commute is basically an hour, and if I don't get the costs reimbursed I simply do not take the job. It is bad enough that I lose that time as it is (as I argued above, it is hardly akin to leisure time).

As for the topic at hand, I've spend a good amount of time and money on e.g. old UNIX hardware (such as SGI Indy/Indigo 2/Octane, Sun Ultra 10, and some DEC Alpha machines) back in the start of this millennium. It was costly and bad for my electricity bills, and it took me a lot of time to play around with old platforms. I had a lot of fun though. And I'm not sure you can benchmark "fun". Nowadays, with solar energy on the rise, it might actually matter less to have these machines running. Except for in the summer. The additional heat would kill me.

Highly agreed on the commute time formula.

Learning to think about time spent on getting ready for work and commuting to and from work as a direct extension of my working hours changed the way I looked at jobs and approach salary negotiation. It's so easy for someone to ignore that cost if they haven't thought about it, and so hard once they have thought about it :)

"I learned how alt-coin mining works, first-hand" could easily be seen as a worthwhile experience.

Because if you normally heat your house through cheaper means (wood, natural gas, etc.) like most Americans, then it's still going to add a lot to your power bill.

But in the US, the time of year for heating your house with wood,natural gas, etc is the cheapest time for electricity.

Do electricity prices vary throughout the year? I don't remember that being the case when I lived in the US, and it's not the case in Ontario. We have time-of-use pricing that swaps the mid-peak and on-peak rates, but that doesn't affect the total charge very much.

Utility companies offer a product of supply and demand. During the middle of the day in the summer in Texas, demand is at its peak as everyone runs their A/C full tilt. That's the most expensive unit of electricity, so the pricing reflects that. Everyone knows that you don't run your laundry/dishes during that time. Winter time, most places are heating with gas, so electricity demand is just never as high so the prices are cheaper. Yes, some pricing options claim they are giving "free nights and weekends", or avg billing that "lowers" the summer rates while "raising" the winter months to keep it on average the same per month. That doesn't actually change the rate per KWh at the time. It's like buying car with the squeezing the balloon analogy, squeeze the price on one end the numbers bulge somewhere else.

Only makes sense if you don't have a heat pump.

However, electricity at least has the potential to be generated by solar, wind, hydro or nuclear; most people in North America are heating with natural gas or even heating oil, which by definition can't get to carbon-neutral.