buttMode allows you to toggle between two sets of video settings in order to alleviate some of the lag experienced during world bosses or other events where there are tons of other butts around. The performance settings that get utilised are lower than the minimum allowable through the factory carbino interface. That's really all there is to it, tons of people have been nagging me to put this on curse so, here it is.
The latest version includes a raid buttmode and ULTRAbuttmode. Try them out.
This can also be macro'd via slash commands, they are as follows:
/bmon
/bmoff