More than half (54%) of Americans say they have started a side hustle to supplement their primary source of income in the past 12 months, according to a MarketWatch. survey. These days, almost anyone can find a side hustle that fits their lifestyle, talents, and interests. Use a beloved family recipe to make a snack. Make it your collector's hobby in a resale business. Get over your creativity block with a service that helps other people do the same.

But starting one side hustle with the potential to become a full-fledged business often means significant investment of time and capital upfront, and there's something to be said for a side hustle that requires minimal effort—the kind that's so mindless that NO doing so is tantamount to throwing money down the drain. A safe way to passive income success? Take advantage of the assets you already own.

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