Fostering creativity in User Interface (UI) design is challenging for innovation. This paper explores the combination of model-based approaches and interactive genetic algorithms to foster the exploration of the design space. A user task model is given in input. Magellan produces sketches of UIs that aim at inspiring the designer. Later on, appropriate tools may be used to tune the right design into the design right. Magellan is a proof of concept that deserves further exploration. Currently it is implemented using COMETs but it is not dependent of this technology.