7 models for doing business online:

1. Physical goods: Stuff you have to deliver offline.
2. Publishing: The sale of data, whether it be digital or   physical books, entertainment, videos, software, databases, or  any other form. This is the only pure online model that  involves hard goods that doesn't fall into the Physical model.
3. Community: you're selling access to a group of other people  with similar interests.
4. Leads: You get ‘em, then you sell ‘em.
5. Traffic: This one confuses people. It encompasses a lot of  methods, but the product comes down to one thing: You get paid  for sending visitors to someone's site.
6. Advertising space: This specifically refers to ads you get paid for based on time posted or number of exposures, not on results.  Results-based payment puts it under leads or traffic.
7. Services: Personally rendered or via software. It's something  you (or your staff or computers) do, not something you deliver.