v_idlescale
This variable controls the amount that the screen should sway automatically. When this variable is set to a value above "0" the screen will start swaying in all directions, similar as if the player was drunk of had a concussion. If you want to have some real fun, set this variable to a value of "100" and run around some maps. The larger the value for this variable the more the screen will sway from side to side.
0
Disable automatic swaying.