Web-based laboratories have become so popular in educational institutions for the great benefits these labs bring and ease of use. They have been successfully implemented in a wide range of subjects, but we still need to build training facilities for the uncovered/new branches of learning. In general, the structure of the laboratory varies depending on the subject area; however, in many cases, especially in the case of ICT subjects, it is possible to use the same configurations for more than one course-topic, Networking and Internet Security for example. This means that we only need to create a "prototype" then we can have as many labs as we wish by making "copies" of it. This is not possible with all laboratory-types, but certain technologies make it doable. In this paper, we describe how we used Virtualization Technology (normal and nested) to achieve this successfully. In our system the laboratory components are constructed using Virtual Machines, and then packaged to make one prototype from which we could create a number of labs for different ICT courses.