15Oct/070
ClusterSSH
I just found ClusterSSH, and I wish I had found it earlier. ClusterSSH allows you to send the same commands to multiple SSH connections / servers at the same time. This would of been really useful in the past when I have previously installed firewalls and security updates to 20 odd servers separately.
Usage: host:/# cssh one two three
This will provide you with one console to enter commands to the three connected SSH hosts.