I work with a lot of technologies, and one of the ones I use the most is UNIX boxes for hospital's systems. Well I was given a task to basically delete a domain one of my clients wasn't using, so I went ahead and started. Well.... not sure how many of you do unix administration, but here's what happened: I was deleting some of the folders, and since it is multiple of them I just made a series of statements to do it for me, and then paste them onto the terminal. I do this a lot to document my commands, or to edit them easier. Well, I had done some manual deleting already, and moved to a folder where I had just deleted some info that ALSO contains vital stuff for another domain currently running on that node. Well, I ran my command, and apparently there was a TAB at the end of the command, which in Linux, auto-completes the path for the only available folder. Which in this case... was the domain they care about.
So after an hour of damn nearly crapping myself, I got a hold of the backup team and hopefully we will restore the filesystem I just hosed. Great. Now I feel like an idiot.
Have a dream machine for your trouble.