Collaborative work environments for scientific knowledge have many applications in research as well as in education. Such systems already exist (e.g. Wikipedia and PlanetMath), but they do not offer all the services users would like to have. Starting from semantic markup of knowledge as a prerequisite for services like dependency management, intelligent navigation and search, and for knowledge reuse by web services, I work out why a semantic wiki is an appropriate platform for integrating these services and how to entice authors to contribute their knowledge into such a wiki by sharing the benefits of the services that exploit the knowledge with them. While most semantic wikis allow users to create hypertext with typed pages and links, the types being defined ad hoc or imported from arbitrary external ontologies, my approach is to tailor the wiki to scientific domains by incorporating both domain-specific semantic markup languages and their system ontologies and specifying servi...