For those of you who use dvorak, you might find yourself wanting to switch back to QWERTY on the fly. Say for instance you want to play a game that arranged its controls assuming that you were a QWERTY guy, or you want to let your friend check her email without a lot of fuss. There’s an easy solution to this! Just run
setxkbmap us,dvorak -option grp:sclk_toggle
This handy little command will toggle between standard layout and dvorak layout whenever you whack the scroll lock key! Useful, huh?