I've always wanted to sell an ebook entitled "The easiest way to get rich", which would contain a single sentence saying "Sell a book called 'The easiest way to get rich'".
Joking aside, there are plenty of business opportunities around, you just have to keep your eyes and ears open. I'm guessing a lot of people here will reccommend blogging (and so will I
), but as Alvin said it takes a long time of consistent effort to start earning a decent amount. It can be a real slog sometimes, but overall it's very enjoyable.
Llisten to your friends. Lots of people have business ideas that they're not sure what to do with, so give them a hand. Perhaps go in as a 50-50 deal, or act as a consultant to help them get started in developing a web presence. Use your experience with these sales letters and use it to help other people.
Best of luck!