Based on a comprehensive analysis of existing grid portals and problem-solving environments, Astrolabe, a feature-rich grid operating environment built on a finetuned client/server architecture is presented in this paper. In Astrolabe, a dynamic portlet container is deployed at the client side to provide portlets with more powerful runtime capabilities such as rich interfaces, local resource accessability and offline usage, comparing to the JSR-168 specification. A workflow designer is built upon the portlet container to provide integrated workflow modeling capability. Moreover, server-side components are also employed to enable portability and collaboration among users. The main contribution of this paper is bringing the aforementioned features as a full package, which could improve the usability of current grid computing environments. Eclipse RCP is utilized for the implementation of Astrolabe to leverage the state of the art of rich client technologies.