If you are a professional photographer, or have a real flair for photography, then selling your images on other sites could be an idea. This could be done alongside your own photography site, as it is a good way help get your work viewed by a wider audience. There are numerous stock image websites to contribute to, but choosing a popular high-end site like Shutterstock should ensure your photographs make you some money.
Great list! I have another to consider that I personally have 35+ years experience providing. Clean up litter outside commercial properties on foot using inexpensive hand tools. It’s almost as easy to do as going for a walk! I started doing this as a side gig in 1981 and soon grew it into a profitable full-time business. I share my experience in my book, Cleanlots.
If you’ve got some free time and don’t live in the middle of nowhere, becoming a Lyft driver can be a very lucrative side hustle that allows you make money fast. And right now, they’ve got a promotion going on where any new driver will instantly get a $300 bonus after completing their 100th ride. If you start now and hustle hard on the weekends, you can probably unlock that bonus within a few weeks of driving (and that’s in addition to your normal earnings).