Cash-flow muses
mishmax: I have one of these businesses. Took me 2 months to build the product (on the side, after my full-time job). A few more to market and see sales (it takes time to close sales and generate site traffic). It should generate 10-20k this year, hopefully more next.My advice is to focus on a niche market filled with people w/ money, willing to pay for stuff. And avoid any market/problem that your typical computer geek would be interested in or aware of (you want to relax on the beach, not code away 60hrs a week fearing some other startup will catch up and take the market away).