Help other people advertise their products

There are always vendors on the web who are looking for new and better ways to advertise their products. If you already have a website or blog that is doing well with plenty of fans and traffic, then chances are such vendors will want you to host their product ads. You could even review or recommend them to people, but make sure you pick products and brands that are established and related, but not competing. You will get paid depending on how many people click on the affiliate links for the products.