Indiegogo lets you invest in potential startups
 

When a kid with a good idea asks you for $20 to fund their new startup, you give that money in the hope they'll do some good. That can sting, however, when they become a multi-billionaire and you don't even get a note of thanks with $20 stapled to it...

https://www.engadget.com/2016/11/16/...tial-startups/