Once you've understood the basics of Semantic Web technologies and how they can be combined with other semantic technologies you can start to really appreciate real-world semantic applications.
This series of lessons helps define what types of use cases benefit from the use of semantics and includes many examples of real-world use cases to underscore the key points.
What Makes a Good Semantic Web Application?—people have used semantic technologies for lots of things, but not all of them are appropriate. What are the key characteristics of a use case that can benefit from semantics?
Applying the Semantic Web - Two Camps—there are two primary kinds of Semantic Web practitioners in the world. Understanding this can help you understand blogs and literature outside of Semantic University.
Example Semantic Web Applications—real-world use cases.
Semantic Web on the Web—applying Semantic Web technologies towards their original goal: the World Wide Web.
Semantic Web in the Enterprise—applying Semantic Web technologies to enterprise use cases behind the firewall.