I love startups
There are a plethora of free resources online to help you get started and if the resources you need aren't free, the costs are minimal since there are so many services offered to help a new site owner get started. The real hurdle is assessing your own resources, defining a need that people have, and coming up with a product or service to fill that need. It can almost be anything because you can make money selling just about anything on the internet. Below are some past projects that I've worked on to help move small ideas online. There are many that are service based while some are online retail shops. If you are going to do a online retail site, take into consideration how you will procure and manage inventory, ship products, and offer customer service. If your project is service based, keep in mind what need you are trying to fill and stick with it.