I stake and lend cryptocurrency (stablecoins and blue-chip coins) on lending protocols and exchanges, and am at around $500 a week.
Not really a side-project per-se, but I do quite a bit of calculation on ROI, where to move what share of my funds to, and occasional yield-farming strategies so it does take a up a good bit of time
The goal is to have that stable enough so that I can quit and focus on my actual side projects that I am hacking on after work
Don't want to share the exact amount but for stablecoins you can get 8-12% APR and that's as 'safe' as it gets without having to deal with price fluctuations. So if you were to convert $100k savings into stablecoins, you'd have a return of $230 per week (100000*12/100/52)
For yield farming you are dealing with higher risk, but you can easily get 50%+ APY on liquidity pools, compare that with the 12% above and it's not too hard to get to $500 a week
Not really a side-project per-se, but I do quite a bit of calculation on ROI, where to move what share of my funds to, and occasional yield-farming strategies so it does take a up a good bit of time
The goal is to have that stable enough so that I can quit and focus on my actual side projects that I am hacking on after work