As a freelancer, business man or whatsoever the term could fit one of the biggest dilemmas I have had is the pricing. You can not give your time, knowledge and effort for free, but while competing against others, I have found that many customers take the pricing as the first factor. So, here it is a way I have found to make this very attractive without hurting my working effort. I hope this will help others as well.
The first thing is that this technique only applies when you are selling products with a scale scheme. For example, giving a course and billing per participant, building a server cluster and billing per server setup, software licensing, it could even apply for support hours if you know how to deal with that, but I wouldn't recommend for that.