Lessons learned... the hard way.

[tuba-man.livejournal.com]

So, today, I was trying to multitask a little bit harder than my single-core brain could support, and I managed to type "cat - > /outfile" while trying to test something...  that client's server is still down...  :/

Update:  Good news everyone!  The server is back up, only 45 minutes of downtime!
Update 2: That's what I get for freaking out!  An amazingly timed network blip nearly made me have to change my pants.  In a bad way.

And just because I'm in a self-depreciating mood, I have one from almost a year ago:
My first week on the job I was tasked with installing CentOS on a client's box.  I was logged into our firewall at the same time to copy some configs to it.   I got pulled away for a short meeting, then came back, saw that it was done copying and typed reboot [enter].  On the wrong VT.  Oops!

Anybody else have any painful learning stories?