(Works best when you point and say it loudly in the middle of their sentence.)
Excited woman says: "I just bought this Louie Vuitton bag for $20! What a deal! I cant believe that I ..... " "WRONGO! ITS A FAKE!"... said by a truthful male while pointing.
"The NY Rangers are going down!! Game started with 3 fights at first puck drop!
"The Rangers won with a 4-2 lead against the NJ Devils, looks like someone's prediction was el wrongo!"