Linux Client Instructions
If you have Ubuntu 10.04 or Debian Sid, then you can just use the package manager or type "sudo apt-get install electricsheep", although that will get you an old version, it should work fine.
Otherwise, the preferred way to install it is from source.
It should configure itself to be your screensaver, but you can also run it from the command line just by typing "electricsheep". You can also use "electricsheep-preferences" to configure it.