Like writing (above) transcription is another type of work that often equals a full-time income. However, there are lots of sites that accept beginners that don't pay very much for the audio transcribed. While a professional transcriber may not bother with the sites below, someone without the skill to be a professional could use them here and there for some quick extra cash:
#9 Military pension/VA disability. Obviously requires a lot of front end effort in your 20s and/or 30s depending on length of service however once out and receiving it is totally passive with cost of living adjustment included most years. It has changed somewhat with new “blended retirement” plan but even those not staying past first or second enlistments often will get some VA rating. My wife got it on both ends of her service as the Navy paid for med school and then she was rated by VA after seven years active duty.
I prefer assets that make me a high return for the lowest amount of work possible (semi-passive involvement). And assets that pay me in several unique ways. Cash flow is only one way RE makes money for me. I also get principal reductions, appreciation, tax advantages (depreciation), and I control the rental increases on a yearly basis. Plus a majority of the capital is provided by the secondary market on 30 year fixed low interest rate debt.
 @Philip Taylor The point is that this is design is specialized job and is not just a side job. Just because an individual may know a thing or two about the technical aspect of a program does not warrant them to fill that role as a designer. There’s more than just drawing a mark in a program. There’s strategy in brand development, marketing, etc… This is insulting to the creative industry to label logo and branding as a scheme to make extra money.

VIPKID provides an international learning experience to children in China between the ages 4-12. Headquartered in Beijing, the company offers fully immersive one-on-one English language instruction provided online by highly qualified teachers. The curriculum is based on the U.S. Common Core State Standards and uses a flipped-classroom approach to foster creativity and critical thinking skills.