ONLY WORK FOR TAUREN
Begin casting Warstomp and halfway through the cast start straffing (Q or E) and cast a spell (with a cast time). Warstomp will get canceled but the spell you just casted after will continue casting even while you're moving.
How to video made by brbwithflag -> http://www.warcraftmovies.com/movieview.php?id=156429