Can you read my smoke signal now?

On three nights this month, in London's Trafalgar Square, one of the city's great public spaces, two artists brought together one of the oldest mediums of human communication, smoke signals, with one of the newest, text messaging. For the event dubbed Memory Cloud, visitors were invited to send text messages that were then projected onto billows of smoke (well, fog) hovering amid the grand buildings and monuments. The idea was to "animate the built environment through conversation."

Romance seemed to be in the air: there were lots of "I love karen"-style sentiments. Among the hundreds of others archived at the project's Web site: "Come home soon dad. Luv Anaya," "Eat more vegetables," "Act for darfur now," "Kiss me nelson" (now would that be Lord Nelson, whose monument stands in the square, or just ordinary-Nelson, the nervous boyfriend?), "where's david blaine?," and "this makes me feel sexy."

The driving force behind Memory Cloud was a two- brother team of artist-architects, Theodore and Stephen Spyropoulos, who together run the experimental design practice Minimaforms. Theodore is also a visiting research professor fellow at M.I.T.'s Center for Advanced Visual Studies.