One thing I always thought was really neat when I learned it is the "unless" conditional. 
if (-e !"/$home/.ssh/id_dsa.pub")

[download]
becomes 
unless (-e "/$home/.ssh/id_dsa.pub")

[download]
Once you grok that, you can go one step further and say 
if (-e !"/$home/.ssh/id_dsa.pub")
{
    `ssh-keygen -t dsa`
};

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becomes 
`ssh-keygen -t dsa` unless (-e "/$home/.ssh/id_dsa.pub");

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Update: Bad advice withdrawn

In reply to Re: Ssh Keys by andyford
in thread Ssh Keys by j^2

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