Not exactly a Garak moment but...
Worf: At the first sign of betrayal I will kill him, but I promise to bring the corpse back in tact.
Sisko: I hope you're joking
Worf: We shall see.
Garak just being around brings out the best on the characters around him.
Garak: Lying is a skill like any other, to maintain a level of excellence you must practice constantly!