Can you give an example of when it would be appropriate to use a web service as opposed to a non-serviced .NET component?
Services which help in stock trading by giving analysis of market trends could best be executed as a web service. The reasons are
1. Such a web service would be simply discovered by potential customers when they need it.
2. It will need minimal setup on the client machines
3. The updates to the system will be automatically available to all its consumers, without any requirement to deploy the updates on their machines.