Yeah, knocking units off of ledges is always fun, especially when I'm not trying to do so. I also enjoy it when somebody attacks one of my units, misses, and is killed my my unit's Counter, always cool.

As for all around funny stuff though, my personal favorite would have to be the scene where you discover Worker 8. "Beat Mustadio up" and "Dance" had me laughing out loud the first time I saw it.