Funny Moments: Duncan getting bored during the speechifying at the Tower of Magi and sneaking off to do some stealing, and ultimately winding up boinking a mage who'd been eyeing him up earlier. Funnier still because his commanding officer catches him doing this.
The scene in which the party leaves Nicolas to die in the Fade so that he can stay with his dead lover is also a fairly huge one. Honestly, most of the scenes in the Fade are this to some degree.
When Kell sacrifices himself offscreen by leading the darkspawn away from the others. Hafter refuses to leave his side. "One last battle, boy?"