While it is true that we (techies, rationalists, etc.) have the opportunity to catch a gold rush by becoming early adopterst, I suspect survivorship bias is at play. There are plenty of people who try to systematically 'grind' on such opportunitities but it doesn't pan out for many of them - I know some people who used to mass-register domains, and made a neglible profit in the end, people who jump on all sorts of altcoins, programmers who join a promising startup, where they sacrifice salary for equity, etc. Additionally, I also started messing with bitcoins in 2011, and while it has been quite profitable, I have made less than six figures, since I wasn't very serious about it at the time. And yes, in retrospect I can say that I should've put more money in (and kept them in bitcoin), but if I follow the same line of reasoning with all the seemingly-promising things I see, I might very well go broke.
I wish I was already an experienced gold rush spotter, so I could explain how best to do it, but as indicated above, I participated in the ones that I did more or less by luck.
Indeed, luck seems to be a big part of it, and the main action that you can take to facilitate the process is probably to put yourself in the right circles, so you can hear and look into innovations early on. This, however, is something that you and many people on here already do, and I doubt that you can easily find another intervention that will have as big of an impact on your chances to participate in a gold rush.
if I follow the same line of reasoning with all the seemingly-promising things I see, I might very well go broke.
Nobody has come up with another example of something that meets my definition of a tech gold rush, so these things don't seem to happen very often. I suggest keeping an eye out for them, but set your standard of "seemingly-promising" high enough so that it's triggered only rarely.
Another useful tip may be to look for entirely new asset classes, rather than something similar to the last big thing (altcoins or startups). Before domain names and Bitcoin, who thought that entries in a lookup table or a decentralized currency could be an investment asset?
In early 2000, I registered my personal domain name weidai.com, along with a couple others, because I was worried that the small (sole-proprietor) ISP I was using would go out of business one day and break all the links on the web to the articles and software that I had published on my "home page" under its domain. Several years ago I started getting offers, asking me to sell the domain, and now they're coming in almost every day. A couple of days ago I saw the first six figure offer ($100,000).
In early 2009, someone named Satoshi Nakamoto emailed me personally with an announcement that he had published version 0.1 of Bitcoin. I didn't pay much attention at the time (I was more interested in Less Wrong than Cypherpunks at that point), but then in early 2011 I saw a LW article about Bitcoin, which prompted me to start mining it. I wrote at the time, "thanks to the discussion you started, I bought a Radeon 5870 and started mining myself, since it looks likely that I can at least break even on the cost of the card." That approximately $200 investment (plus maybe another $100 in electricity) is also worth around six figures today.
Clearly, technological advances can sometimes create gold rush-like situations (i.e., first-come-first-serve opportunities to make truly extraordinary returns with minimal effort or qualifications). And it's possible to stumble into them without even trying. Which makes me think, maybe we should be trying? I mean, if only I had been looking for possible gold rushes, I could have registered a hundred domain names optimized for potential future value, rather than the few that I happened to personally need. Or I could have started mining Bitcoins a couple of years earlier and be a thousand times richer.
I wish I was already an experienced gold rush spotter, so I could explain how best to do it, but as indicated above, I participated in the ones that I did more or less by luck. Perhaps the first step is just to keep one's eyes open, and to keep in mind that tech-related gold rushes do happen from time to time and they are not impossibly difficult to find. What other ideas do people have? Are there other past examples of tech gold rushes besides the two that I mentioned? What might be some promising fields to look for them in the future?