Ask HN: How do you handle multiple side projects/ideas?

I'm currently burdened with passion for multiple ideas at once - all have been started in one way or another. I've always been a strong believer that people can't really work on multiple things at once. That, to succeed, you need to put all of your energy into one thing.

I have a lot of trouble actually doing this, though. When I think of something, and truly believe in it, I start it. Once I start something, I have to finish or it will haunt me until I do.

I currently have 3 projects running right now in development phase, all of which are very complicated and require 100% of my attention.

Does anyone else have this issue? How do you approach it and convince yourself to scrap all but one? I'm going mad! :p