Firewall is an interactive art installation created by Mike Allison and Aaron Sherwood. At first glance, the piece is somewhat unimpressive – a spandex sheet stretched over a large frame. But when switched on, this spandex sheet becomes a membrane that combines music, motion and metaphysics at the touch of a human hand. When untouched, the sheet shows orange-red lines running vertically across its surface. When the membrane is touched, the lines dance like fire, rippling in reaction to the movement of the user’s hand.