I keep hitting a block where I can't find a SaaS idea that could guarantee this revenue that wouldn't require a lot of upfront effort in development. I think I'm better at designing an app and improving its marketing strategy than actually writing the code, but I can't hire a developer.
I read the gospel (ahoyhere's blog, http://unicornfree.com, closer to us mere mortals than 37signals/svn) and understood it as: find a group of people, watch them in their natural habitat, pay attention to the problems they mention having, and if you know a way to solve that problem, turn it into a product.
I still haven't had a solid idea. Every time I identify a group with a problem, the solution is something that would take a lot of upfront work for me on my spare time. I know there's an idea or problem I'm overlooking, but I can't find it.