Not an adult, worsening home situation - which wasn't great in the first place, so could really do with quick money. Assume skill/competence is not a barrier.
The best method know of is ImmuneFi's bug bounties: https://immunefi.com/explore
Anyone who has the skills necessary to find a vuln can instantly convert them into money, without any barriers like formal credentials or onboarding processes (for which I have no time).
What other opportunities (in any sector, not necessarily CS-related) share the same characteristics?