This paper discusses the requirements of Interactive Geometry Systems (IGSs) and how they can be fulfilled, explains how a geometry tool can benefit from the Internet, and presents Cinderella's Cafe. Cinderella's Cafe is a new IGS with a high mathematical background that uses the most general mathematical models whenever possible, is highly portable and Internet-aware, and allows direct export into World Wide Web pages and the creation of interactive exercises. Topics discussed include: (1) an overview of interactive geometry; (2) key features of IGSs, including dragging objects, macro operations, loci, and additional requirements; (3) features of Cinderella's Cafe, including the use of a general approach to geometry, possibility of multiple views, Euclidean geometry support, hyperbolic geometry support, and measurement of angles and distances; and (4) using the Internet in education, as it relates to the design of Cinderella's Cafe, including choosing the right language, instant availability, example databases, and interactive exercises. Six figures illustrate: correct behavior of the radical axis; central projection of points on the sphere into the plane; exploring conic sections; constructing parallel lines; hyperbolic geometry in Cinderella's Cafe; and an example Web-page showing the use of Cinderella's Cafe. Contains 23 references. (DLS)