Product and service sales income

Pick a product or service to sell on your website or blog, markup the price, and earn enough money to pay for your expenses. The remainder is called profit. Sounds simple, but some people come to a halt at the beginning by asking what product or service could they possibly sell? Don't think too hard about it, the answer could be right in front of you. And how much of a markup is selling something that was basically free to you? Pretty big I suppose....