My erm favorite was when I was at university. I was building an application (I don't recall what) and as I wasn't root I had built it with
So I could install it to my home directory. Unfortunately it installed into
instead. Naturally to delete it as start again i executed
rm -rf ~username
In the source directory.
I wondered why it was taking so long....
However my worst one was when I was working with a solaris workstation and after getting it all setup we wanted to wipe the configuration ready for live config. So I executed
Agreed to the warning message and instead of the machine rebooting and going back to "factory defaults" The xterm window simply said
connection closed by foreign host.
Moral of the story Don't ever leave a root shell open on another host! EVER!!