Wei Dai, one of the first people Satoshi Nakamoto contacted about Bitcoin, was a frequent Less Wrong contributor. So was Hal Finney, the first person besides Satoshi to make a Bitcoin transaction.
The first mention of Bitcoin on Less Wrong, a post called Making Money With Bitcoin, was in early 2011 - when it was worth 91 cents. Gwern predicted that it could someday be worth "upwards of $10,000 a bitcoin". He also quoted Moldbug, who advised that:
If Bitcoin becomes the new global monetary system, one bitcoin purchased today (for 90 cents, last time I checked) will make you a very wealthy individual...Even if the probability of Bitcoin succeeding is epsilon, a million to one, it's still worthwhile for anyone to buy at least a few bitcoins now...I...
This comment ended up more interesting than I expected when I started reading it. Did you write up your progress journaling anywhere online?