Wait, it jumped up again as I was writing. Now he's at $7,538,783.96. Another $18,000 in a few seconds...
A son asks his dad for $10.00 in bitcoin.
The dad replies, "$9.87? What do you need $10.76 for?"
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I made a nice chunk of fiat a few years back with bitcoin - in the $100/btc days, late FPGA era/early ASIC era. I bet, hard, against Butterfly "Two More Weeks" Labs, and came out nicely ahead.
Once the ASICs were announced, the FPGA based miner sales cratered, so the people building them stopped building them. And because BFL was being silly, I discovered there was some insanely great demand.
So, I took a bit of a gamble and commissioned another run of FPGA miners from a guy. I sold them for a very nice profit, mostly on eBay (nobody was willing to deal with eBay/PayPal for cryptocurrency miners, but I had a high feedback rating, had sold a ton on eBay over the past 15 years, and will put up with a lot of crap). I did have to deal with eBay and PayPal, prove that I had the inventory I stated, and dealt with some temporary fund freezes, but it all resolved and I came out ahead.
Then, I had a chance to pickup some used FPGA miners from a farm that was being shut down. So, I bought some btc from a guy I knew, and made an order of these. Hindsight being 20/20 and all that, I should have just held the BTC, but I was looking for low risk ways to profit on BTC, and selling hardware I got for well below market value was a pretty good bet. There was very, very little downside risk. So, I sold a bunch of these boards either as standalone boards or in cluster form (I sold one guy a $30k cluster that could, at the time, mine north of 0.5 btc/day, and if him and his brother held onto some of the product of that, they should be very well off at the moment). At the peak, I was selling a bunch of these for about 4x what I'd paid for them.
Eventually, BFL shipped something, and the FPGA era tapered off. I sold my remaining stock for about what I'd paid (which was my exit plan - I think the last batch went to a guy doing Monte Carlo simulation or something), and moved on with my life.
That was informed by my reading (admittedly too late to really understand bitcoin early on) on the history of commodity currencies and gold rushes. What I recognized was that the people who made out like bandits in gold rushes were
not the miners. They were the salesmen selling pickaxes, shovels, jeans, tents, food, etc. Bitcoin was transitioning out of the "individual miner with a shovel" era to "teams of miners with some better equipment" era, but you could still get lucky with a shovel, and I sold those. We're now deeply, deeply into the industrial mining era, so there's no opportunity to do something like that again, but bitcoin did follow the gold rush model fairly accurately.
It was nice, but I cashed out most of the BTC as I mined them in my test clusters. I was looking for something with quite low downside risk. That I'm not retired from my job right now should let you guess that I didn't hold onto enough of them...