Killed by Death.
Angelus only has two little appearences, but that's a reason to like them even more. The episode is average to say the least and Angelus on screen is already the highlight.
His little fight with the Slayer right in the beginning is full of dripping sarcasm (love that) and the dialogue between him and Xander in the hospital is a little sword fight without swords. You should decide whether that's a good thing!