I just saw something in my good friend Reb Y.'s blog (which is criminally under-posted on) that struck me as a very powerful tool for use when faced with nisyonos (emphasis mine):

If a Jew is faced with the choice to worship avodah zarah or die, even if all his senses tell him to bow down, if logic dictates that he bow down. It is his inner emunah that screams, "How can you? How can you deny Hashem's existence for even a second? How can you not give up your life for Hashem?" This voice is louder and will defy any common sense.

The Tanya goes on and brings this into the everyday life of a Jew. When faced with an inclination to do something against the will of Hashem, remind yourself of this. You would be willing to die for Hashem's will. How big is your taivah to do wrong? Can it be bigger than dying? If you're willing to die for not being separated from Hashem for even a second, you should be able to overcome any desire you have and not go against His will.

Awesome.