This is pretty amusing!
moo
Awwwww, it’s already over. I’m too late!
[del]There’s a link to it at the top of the page.[/del] OK, phi2dao beat me.
ping
echo
… Weird, I tried ‘echo’ and it didn’t work.
I get:
guest@xkcd:/$ echo
Echo ... echo ... echo ...
sleep
Should have lit your lamp first! Then you could have got somewhere for a nice nap.
find
find kitten
goto
Interesting that “rm” treats “blag”, “blog”, and “about” as directories, but not “fora”, “forums”, and “store”. I wonder why that is.
Also, just to add to things that’ve been tried, there’s “emacs” and “vim”
Apparently, he added some as the day progressed…that would explain why echo never worked when I tried it.
Nothing seems to work for me at the moment.
It won’t let me type anything at all.
Yeah, seems to have been disabled. 
Oh, poo. I only heard about this after it was taken down. I saw it on the day (figured, if any site would be in the April Foolery mode, it’d be xkcd, especially since they aren’t updating the comic that day), but, having forgotten all the cool things I could do with unix (my last unix command was typed about 15 years ago) and the like I didn’t use the interface to its full potential.
:sniff:
It’s still accessible via a link at the top of the page.
It just wont let you view the comics. Otherwise it works fine.