I know a few people doing this, one person in particular who has discovered a near-zero-risk quirk that can be exploited with algorithms for fractional %age gain per transaction/cycle/(kind of being vague here sorry). He's been able to deploy large $MM amounts of capital to create significant gain nonetheless.

However none of them will talk about it, certainly not on HN. I'm mentioning it simply to highlight I think you'll find an anti-selection bias by asking here.