I was trying to fix a broken backup process on an AIX box, and found that there were a ton of stuck Legato processes on the system. Rather than kill each one individually, entered the killall command to get the correct syntax to kill all of the processes with legato in the name.
In Linux, entering killall gives you the syntax on how the killall command works. In the old version of AIX this system was using, it killed EVERYTHING with no warning and basically rebooted the box. That's not usually not a big deal, except that this was the primary SAP database server for a Fortune 500 company. It took the DBA's about a day to clean up the mess.
The system was clustered, thankfully, but it probably cost about 10K in labor to clean up the mess.