"What products/site could you build that charges $30/month (SAAS) and can get 500 signups. Just that would get $18k/month in revenue [...]" Well if that's the

"What products/site could you build that charges $30/month (SAAS) and can get 500 signups. Just that would get $18k/month in revenue [...]" Well if that's the process then why not just up the ante and figure out how to make some absurd amount of money? The reality is you're not going to be able to answer that question with any degree of accuracy as to make the exercise meaningful. All you can do is put something out there that you believe has potential and gauge how profitable it is and consider the growth potential in the future.