I bought 1000eur worth of BTC a few years ago (at a bad time market-wise, I may add) just for fun, which I have intermittently traded (as in selling or buying maybe once a year if I notice the market is particularly high or low). I withdrew 1000eur in profit a couple of years ago, so anything I make now is gravy. My trading account is currently worth ~13000eur. Compared to the returns on my weekly lottery ticket and the premium bonds I was given decades ago, I'd say bitcoin has been a sound investment so far, wish I was brave enough to invest more than beer money in it.