I used to drop mage portals just infront of the existing portals in Dalaran (or an org one in the empty space to the left of the existing one). People raging that portals were broken. Worked extra well for people who didn't read patch notes when they removed those portals.
Early Cata I would call out I was opening lockboxes at org inn. People would group up to find me > Tricks and slap gamon > Gamon destroys poor unsuspecting victims. Used the cenarion guy near Zeppelin tower in old org with MD to kill various lowbies.
Stun and/or spell lock + full dots on MC'd people. Killed a few folk on grand vizier(?) for giggles.