[K12OSN] OT linux utility to run command on many systems simultaneously

[dalen]

I seem to recall reading about a linux utility that can run a command on 
many machines at once, but I can't remember the name.  Does anyone know 
of a utility like this?  There are many times that I need to run the 
same command on many machines.  For example, say I want to add a new 
user "joe" to machine moe larry and curly.   I would then run "some_util 
adduser joe" and the user would be added to all machines listed in a 
config file via ssh.

Thanks,

Dale