Seth Godin just gave a link to Kevin Kelly post "More than free" about eight ways of making something worth charging for.
He mentions the following:
1. Immediacy - get now or at least earlier than others.
2. Personalization - generic version is for free, customized one is not.
3. Interpretation - software, free, the manual, $10000.
4. Authentacity - how much are you ready to pay for a trueness certificate?
5. Accessibility - low access cost, how much are you ready to pay for it?
6. Embodiement - making services r intangible goods tangible.
7. Patronage - audiences want to pay the creators.
8. Findability - makeing money by helping the audience find works they love
I love the article.