Extortion.

(Not really.)

You could make good YouTube videos and get a good viewer base who will end up clicking on ads (if and when you monetize your videos), earning you some money. DON'T ask/beg for subscriptions. Begging gets you nowhere, but saying something like, "If you like what you saw, feel free to subscribe to stay in touch with my videos."

You could sell stuff on Craigslist/eBay.

You could (with an investment of $10+) start a server, make it great, get a good player base, and accept donations for non-op perks, like /hat, no teleport delay (if non-PvP), more /homes, etc.


I'll edit this to add more ideas as they come to me.

Webcam show

YEW CAN HAX ALL T3H B4NKS!!!!!!11
Just kidding, I'd say making logos/art is your best bet, depending on your age, because at the moment, people aren't too accepting of young YouTubers.

Make a server, then after getting a good player base, set up donations like i did. I made over 100 dollars, and then used all of it to upgrade the hardware of my server. So as long as you don't make a server just to leech money from people, its a good way!

-Youtube
-Building something that is really cool.making a texture pack,mods (adfly)
-Graphic Designs
-Games
-Website maker

Youtube
Hosting a Website
Making art for people

There is a some ways but it takes a lot if work. Here are two:

Youtube
Website

(If i am not right please tell me)

Edit:

Here is some more

eBay

you can try making high quality logos for companies that need them, my friend does that