I pay attention to the questions my clients ask and the pain they're feeling, then write about that because I assume other potential clients have the same pain. Occasionally I write about something just because it's been on my mind. I specifically the strong urge to write for other people like myself (that is, other marketers), because they're never going to become my clients.

I like the idea of having a tool that acts as a lead generator, so long as it doesn't take too much time to make, because there's no guarantee it will work.