How to Find a Niche in Content Locking or PPD?

I am active in around forums and I saw vast number of people having a hard time finding a niche to
content lock or to put in their PPD site.
Most of these people don't even know what is a niche. So, if you don't know it. I will not tell you.
Go find it yourself. Internet marketing is a lot harder than having 5 - 9 job. Anyways, I will not explain that.

Do you ever think? What KIND of niches works with Content locking?...

How to Find a Niche in Content Locking or PPD?