Yes. I've developed a simple strategy that algorithmically trades cryptocurrencies (mainly ETH and BTC because volume, but it would apply successfully to any of the others as well). The strategies are simple, they are based on simple technical indicators, and result in about 2 trades executed per day. The strategy can be applied to "normal" equities as well but it performs particularly well on cryptocurrencies due to the amount of volatility in the market. Also the amount of freely available data for cryptocurrencies makes implementation much easier (and cheaper).
Over the last 3 months, January to March, I've had a return of just under 50% (in spite of the massive down turn in the crypto market). Which sounds great, but I only turned it loose on about $250 so we're not talking about buckets of money here. With higher amounts of capital you run into other issues that would need to be addressed in the algorithm/strategy.
I've often been told the same thing (you can't beat HFT, large firms, etc) but in the end it's not about beating them. It's about finding a strategy that works, that can be automated, and having the patience to let it run and do it's thing. I only trade about 1 to 2 times per day (not HFT) and only rely on fundamental data (no inside info, no "get the data before everybody else and act on it", etc). Keep it simple.
Happy to answer any questions.