Asp.net 2.0 has a built-in feature for creating multi-threaded page AKA AsyncPage, but for Web Service threading, there are no out of the box support. The following code snippet will show you how to create a multi-threaded web service. For the sake of the example, let us assume that we are creating Video Search Service, which will search different sites such as YouTube, MetaCafe, and DailyMotion for a given keyword and returns a composite result. Since this search can be done independently, we can...