Write an e-book.
Information is something that people want and people need.
If you happen to have knowledge or experience in certain fields, write about them in a form of an e-book and sell it online.
It is much easier to sell e-books than to sell books, and don't think that your topics are ridiculous.
Write down things that you usually do and figure out which ones people might find useful.
Play online games.
Remember how it used to be a dream to earn money doing something you enjoy? Well, this is definitely something enjoyable.
Find one game that you're very good at and look for sites that sponsor these online games that have rewards for winners.
Winners get money from other players who paid fees in order to join the game.
Lots of people make money keeping their blogs, and the whole activity does not even feel like work, if you're someone who writes regularly.
This one actually works by having companies place their ads on your website.
What happens is that when people visit your site and click on the ads, you get yourself paid.
There are many other ways to make money on the internet part time, these three are just some of them.
Remember that the general rule to making money is really to know what you can do and find opportunities with which you can use them.