Called Amazon Mechanical Turk, this marketplace offers you tasks which require human intelligence and interaction. You can do these from where ever you are in the world. Some are quite simple but repetitive. Others require analytical and critical thinking skills. But the ability to do these at your leisure can fit a flexible schedule. You will need to pre-register and have your app approved.
To check out if Mechanical Turk makes sense for you, go check out https://www.mturk.com