Don't Shout "Fuck" in The Data Centre
A long time ago, I was moving an AlphaServer 4100 from FDDI to Ethernet; around about the time that auto-negotiating the speed, etc. was "problematic". After realising that autonegotiation hadn't negotiated anything mutually workable, I let loose a loud "fuck" (as stress relief) and started nailing it in the firmware environment (can't guarantee that but it definitely required rebooting the whole thing - which wasn't that quick). At each failure, I'd let loose another "fuck" until the network manager came across and suggested I not do that because I was making the director nervous.
That plus other events leads me to the firm conviction that senior managers should be allowed nowhere near the DC when important work is going on.