Find a market first that spends money, then find out what they want and give it to them.

It is certainly easier said than done, but there are a lot of places online where you can do your market research for free. They've done most of the work for you already. You just need to know where to go and what to do to connect all the dots.

Let me show you the process I go through when I'm trying to brainstorm for ideas.

For starters, I'm always aware of trends and current events in the real world. I read several newspapers each day, many magazines, both general and niche-specific, I watch the news, I listen to the radio. Occasionally something that I hear or read will stick with me. I may record my thoughts on my portable voice recorder; jot down some notes, whatever happens to be convenient for me. Sometimes I'll call my office voice mail and leave myself a message.