Demand for products and services varies from person to person, business to business, community to community. High-fashion stilettos don't hold the same appeal for me personally as they might for someone of a different description. Meanwhile, a new business tool or consumer item that might thrill me would be totally irrelevant to someone else.

I suppose you first ought to identify what it is that you can produce or provide ... and what among those choices is it that excites you. Then try to identify your audience and get feedback from people who won't flatter you.