Day1 Machiel and Hayo preparing the 'Wow!' installation. At night. On the Roof. Yeah. Share Facebook Twitter LinkedIn Pinterest E-mail download Wow! is a physical-digital graffiti wall you can draw on using the light from your cell phone, cigarette bud etc. It was developed during Dev Camp '10 by Mark Wubben, Dirk van Oosterbosch, Eelco Wagenaar and Marie-Anne Huiskamp. With: Machiel Veltkamp, Hayo Where was this made?: Mediamatic at Eurosonic Noorderslag