Every player and every DM needs hope. Hope is essential for both character and NPC's alike. Do you have hope? Without hope, you're pretty much doomed in the RPG world. NPC's who are hopeless will turn to extreme measures in order to get hope back. Try to take advantage of that as a plot device in your adventures in order to turn good NPC's temporarily evil, and thus give your players that pesky moral choice dilemma when they have to decide whether to kill or just maim said NPC (they'll most likely kill him if it that NPC doesn't really seem to matter). If your players do kill the innocent NPC who has turned to dark side in order to regain his or her lost hope, lay the alignment smackdown on your NPC's and make them live up to that evil decision of theirs.
I also hope that I will be better the day after tomorrow so that I can do a better post for the letter I.