Playing a Carnage scenario, my friend deployed a Vindicare Assassin right on the objective. I deployed the Decapitator with the instructions: "Behind the Vindicare". After finishing the Assassin off, he continued to lurk on the objective. A Tau Devilfish sidles up, ready to unload a squad of Fire Warriors, and the Decapitator strikes, knocking the Devilfish's rear in with a single S6 blow. Then some form of IG tank arrives, and guess what happens to its lovely AV 10 rear..
In a game of DE vs SM, I took a silly risk by placing my Ravager out in the open, 18" away from a Devastator squad with Missiles and Plasma. I shoot the Dissies, and take all but the PC Marines out. Needless to say, after his shooting phase, there wasn't anything left... of the Devastators! *evil laugh...*