What It Is Without the Hand That Wields It is an interactive installation by Riley Harmon:

“Mediated experiences of killing change our perception of authentic violence and death. As gamers die in a public video game server of a modified version of Counter-strike, a popular online first person shooter, the electronic solenoid valves dispense a small amount of fake blood. The trails left down the wall create a physical manifestation of virtual kills, bridging the two realities. The title is inspired by the Telefon Tel Aviv song of the same name. ”

[via wmmna]