Rafael Lozano-Hemmer is an electronic artist who work explores the intersections between new technologies, urban spaces, active participation, and what he calls "alien memory". In his most famous piece, Vectorial Elevation, eighteen tele-robotic searchlights were placed on the rooftops of buildings surrounding Zocalo Plaza, the public square of Mexico City. By using a web-accessible interface that provided control of the searchlights, members of the general public were provide the means to design immense outdoor light sculptures. Initially commissioned as part of Mexico's celebration of the arrival of the new millennium, subsequent versions of the project have been presented in Dublin and Lyon.