If today's economy has left you in need of more cash, consider this emerging trend: Millions are using the Internet -- and a minimal amount of time -- to bring home extra bacon. Whether delving into e-commerce or selling ad space on a blog, Internet sellers often benefit from a rock-bottom initial investment, the convenience of working wherever and whenever they please, and the freedom of being their own boss. However, before you quit your day job, it's important to consider the potential pitfalls of selling on the Internet. These include startup time, extenuating costs and stiff competition. "There are a lot of people trying to do the same thing," says Robert Spector, author of the book "Amazon.com: Get Big Fast," a book covering the history and development of the Web giant. "What's going to differentiate the book I get from you versus the book I get from your competitor?" Following are four ideas for turning the Internet into your own personal cash cow, and suggestions for staying ahead of the competition. Making cash online :-