If you've ever played as an EVIL character, what would you say is the most evil thing you ever did in the capital wasteland?

I mean the MOST evil, not your average run-of-the mill evil like blowing up Megaton or flame-throwing Harold to death.

I've done all the usual evilguy stuff, now I'm looking for some new ideas.

I'd say since this is general discussion, I would say

I legit killed everyone I could in both Fallout 3 and New Vegas. You actually notice the lack of people after doing so, especially in NV.