It has been a while since there has been a good round of golf, so I decided to post one. I couldn't come up with a nice interesting math brain-teaser, so I'll post this one.

The Rules
Expected Input-Output
My Swing (83 chars) 
sub a
{
$_=pop;($_=reverse sprintf"%.2f",$_)=~s/(\d\d\d(?=\d))/$1,/g,return re
+verse split''
}

[download]

Enoch

(update: Changed "integer" to "number". Integers don't have decimals. Thanks to xylus for pointing out my err.

In reply to (Golf) Formatting NumberTo Money by enoch

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