[Serious] People of Reddit, what ways do you make passive income?

I'm college bound this year. Until now, I used to do the following.

Collect change lying around the house. Or take from the "change fund" or sometimes from mom's purse. Keep collecting for a couple months. Just tens and twenties, sometimes fifties. (I'm an Indian. 10s, 20s, 50s have really low value in the market)

At the end of about 2 months. I'd have around 1000-2000 bucks. Additionally, I get around 500 bucks to spend a month. I don't really spend that much each month. Maybe a 100 or 200. But I save more than I spend from the 500 I get.

Now there's a shortage of change around the house. So my parents ask, "Do you have any change left from your 500?" I reply in the affirmative and give them about 300-400 in change. **They don't need that much but I give anyway. They need about a 100. I give them 300.

When they return the money( not in change but in proper bills), I ask them to round it from 300 to 500. They do that. Nice parents.

So I make an additional 100-200 bucks on that. Plus I have the repository of change. And the majority of the remainder of my 500 allowance.

When everything settles, I start collecting they leftover change from the pool I lent them. Along with the change that surfaces from my parents money every month. And I get my monthly allowance.

This keeps repeating.

I'm 19. Have been doing this since the last 10 years. Collected 25K at one point. Spent it judiciously, never more than 2k at a time. I spend on a lot of things, like food, use Uber and not public transport, etc without my parents knowledge. I still have a hidden stash of about 15k.

I'm evil

/r/AskReddit Thread