If you haven't checked it out yet, do so before April Fools ends. It's pretty cool.

Edit: I guess I should give a link. www.xkcd.com

 

Make sure you type up help at least once.

 

Also fun is make me a sandwich.

 

Tried that too, huh?

 

Fuck also works.

 

I also tried "terminate humanity", "find nemo" and "play global thermonuclear war", but got nothing.

 

A few more I found:

whoami
pwd
who
more
emacs
vim
make command unrecognizable
date
light lamp
find
find kitten
clear

[Edit: "rm license.txt" actually removed it in my mock-shell. Go figure.]

 

"Go" also works, and you can type just about any word after "Go" for a result.

 

ssh
echo
cat

 

Found a few

Kill
xkcd
man in the hat
cheat

 

Found a few

Kill
xkcd
man in the hat
cheat
sudo
moo
man
look
exit west
exit south
light
buy stuff
lpr
xyzzy
i read the source code

hello joshua

 

go down
shutdown
sudo shutdown
find kitten
locate keys
locate problem
locate joke
locate ninja
nano
asl (do this a bunch)
light lamp
make me a sandwich
sudo make me a sandwich
ping
your gay
more
bash
uname
irc
apt-get moo
sudo rm -rf / (and then try to do anything)

edit:
su
top
sudo reboot

Edit, part deux:
Looks like it's done now. But since we're on the subject, I ran across this a while back:

http://goatkcd.com/ (NSFW)

(If you know what goatse is, you might get a kick out of it's latest incarnation. Basically, they take the last panel of the xkdc cartoon and replace it with the stinger. Some of them can get a bit amusing... (all of these are (NSFW)(NSFW) (NSFW) (NSFW) (NSFW))

http://goatkcd.com/714/
http://goatkcd.com/717/
http://goatkcd.com/708/
http://goatkcd.com/697/
http://goatkcd.com/690/
http://goatkcd.com/286/
http://goatkcd.com/229/

etc... There are actually a surprising number that the joke works for)

 

You can still use it by going here.

 

http://wiki.github.com/chromakode/xkcdfools/commands

They have a couple I didn't see listed.