I was just wondering what you folks did when it came to testing out new site or niche concepts that you want to work on?

The last few months we've been building tons of sample paysites and testing them on our own in-house traffic and traffic from the SE's to gauge how popular certain niches are, i wondered if you folks did anything like this or, if you had any other ideas on how we could test these new niche site ideas better?

Regards,

Lee