Which is the standout moment in HL2 for you? For me there are two, I guess. The first one is the Rvensholm level which gave me the chills first time around. Those leapers give me the heebie geebies. The second is the encounter with the Strider's outside the entrance to the Citadel. I remember cowering under the passageway in the road desperate for an opening to go reload the rocket launcher.

What stands out for you?