Only NCI thing that was a little funny, was a dancing Wall-e, NCI Edgartown is uninhabited, along with almost all of bay city.
If in general, then I've gotten laughter from myself, and other people by messing with a boxbot AV.
Edit: Recently, I had a weird experience with a newbie:
In the four newbie spawn points, Pullman Nix Lewis and Card, The four sims each have their own different bits and pieces of their own, Lewis has a shooting range, and a sandbox
Pullman has a giant sandbox, and a "Real Estate" company that sells Linden Homes
Card has a japanese newbie help area, a mountain, and a small river
and Nix has the Freebie shop, and a water play area.
I was in my spaceman-thingy AV, and was sitting at one of the spawn points, a newbie pops up out of nowhere, and looks for the coolest guy there to ask for help, I was the third. he goes to the first, and the guy is very rude. he goes to the second, and then the second dissapears, he comes to me;
Newbie: Can I have some help?
Me: Sure, what do you need?
Newbie: oh, cool! I went up to the first guy, and he just cursed, as if he was a bossy character from a book!
Then it reminded me of an interesting book I read
Newbie: Is there a place where I can get stuff?
Me: Yes, there are several immideate spots to get stuff for your inventory,
Newbie: Oh COOL! WHERE?
Me: well there's the Nix Bazaar, theres NCI, There's the newbie shop a couple sims over...There are a whole bunch of places!
Newbie: Take me to the bestest spot! Let me buy whatever I can get with your money!
....
Me: Well, they are all freebie stores, so you can use your own money
Newbie: But I don't have any money!
Me: I don't have any either
Newbie gasps: You cheapskate!
....
Me: Do you know what a freebie is?
Newbie: no....but you're still a cheapskate!
Me: okay, 1) I am not a cheapskate, I did not promise anything for letting you use my money, 2) A freebie is an object that someone is selling for no money, for example, I'm selling some Animation Overrides there that cost zero linden dollars.
Newbie: Oh! So you're not a cheapskate, sorry!
newbie wants company, he wants to see if the AVs he like fit him correctly, but he's a cloud to me!
He tries on an Iron Man Avatar
Newbie: So how do I look?
Me: like a cirrus cloud, I can't see your AV it's a cloud to me
Newbie: It's not evaporated liquid that pees all over us when it gets to heavy!
Real life, It starts to rain,
Second life:
Me: Hey, I'll tell you why I can't see you correctly, My screen isn't loading your Avatar correctly, and I need to log out, and log back in to get it set correctly!
Newbie: Well log out!
Me: I can't
Newbie: Why not?
Me: I've got three conversations going on in SL Instant Messaging!
Newbie: Oh, you wanna IM me?
And he tells me his Windows Live account name, so I can IM him.
Me:-.- I give up, you're hopeless.
In the background one of my friends....
Zel: John? Where are you?
Newbie: It's that second guy again!!!
and an argument starts with Zel and the Newbie about TPing out once Newbie asked for help, I tried to settle it after telling him that No, just because he dissapeared from sight once Newbie asked for help, that didn't mean that he didn't want to help him. and then I get involved in it that I eventually needed either of the newbie experts on TG that I know, Glenn Shamen, or RoK Vella, but neither of them were on.
Newbie: I give up! I'm never getting on Second Life again! Just because I'm different, that dosen't mean that you can't treat me like @#$%!
Me: I'm not treating you like that, I'm trying to help you!
Newbie: Oh give it up!
I never saw him again, that was the last time I had that bad of a newbie experience