Martin's response when Cary tells him that he took two fireworks apart to make his own M-80.
Martin: Your obsession with fireworks, and I'm saying this as a friend, concerns me. And my mother.
The banter between the kids at the breakfast diner is funny as well.
"I can't believe we're breaking into the school. Who does that? Nobody does that! Idiots do that!"
The chaos itself is also somewhat funny:
The gas station attendant being distracted by the Walkman over a police sheriff's police car being attacked.
A car dealership losing all of the cars' engines.
Dealer: What am I supposed to do? The insurance company thought I was joking with them! And look! (opens a foreign car's hood with its engine gone) We don't even have the wrench to take that out!
The power crewman first finding entire power lines out and then finding several washing machines being flown into the air, one landing close to him.
20 microwaves disappearing from one's inventory and thinking it was done by Dirty Communists.
During the bus attack, there's a momentary bit of levity from the carnage when Charles is crawling out through the wrecked window and accidentally kicks Cary in the face in the process.
After returning to the town, Charles gets a drink off the counter of a house. He's asked, "Why are you drinking that? It's not even yours!" and he responds, "Nobody cares, we're in a warzone!"
The entire So Bad, It's Good film the kids made during the credits. The ending with Charles clinches it.
Making it funnier are the bits left in of all the real stuff from the movie going on in the background.
Or how the few tidbits of good acting that Alice contributed apparently wound up on the cutting-room floor.
The "recreation" of the train crash. Complete with Charles making explosion noises.
That priceless look on Overmeyer's face when the Colonel tells him to open the bus door and shoot, with the creature right outside in hiding. Followed shortly after by the utterly incredulous driver reluctantly opening the door on the Colonel's orders. For extra dark hilarity, both of them are black guys and look like they're clearly aware of what's going to happen next.
Anytime Martin freaks out, which luckily is ALL THE TIME.
"GOD, Mom, I'm COMING!"
And when Joe and Alice are talking in his room at night. "I'm just in shock at this entire conversation."
"Excuse me, can we get some more fries because my friend here is fat?"
Carey and his firecracker/explosion fetish.
"Are you okay?" Yeah! Except I think I might be having a heart attack right now. And I got a scrape!"
When the alien's ship is lifting metal objects into the air, it grab's a random soldier's gun. The soldier tries to hold onto the gun before giving up and letting go of it, falling to the ground.
This brief moment where the kids go into someone's house as the military starts attacking the alien, and Charles picks up a bottle and starts chugging from it, complete with audible gulping.
From the same scene, after Martin is injured:
Charles: Hold still, this might hurt!
(Martin whines)
Charles: JESUS, MARTIN, I HAVEN'T DONE IT YET!
Before that, when the group decide to split up so Charles can tend to Martin while Cary and Joe go to rescue Alice, Charles and Joe have a meaningful moment before Cary butts in.
Cary: I'm not staying with the girls!
Charles: God, Cary! SHUT UP!
Cary: CALM DOWN!
"I could get back into disco"
Joe slapping Alice to wake her up is funny in a kind of Black Comedy way.
It's remarkably funny that the alien is buff as shit, yet he has mental powers.
