My side gig threshold is set by the local plasma donation center, which will pay you about $70 for 2h of your time, so $35/hour. You can earn maybe $140/week if you don't max out the opportunity, so $7,280 per 52 week year to sit in a recliner and read, watch a movie, or listen to an audio book.
Any idea that can't reliably beat that isn't worth my time, because I already don't sell plasma.