Another solution (TIMTOWTDI), using pack and unpack: 
#!/usr/bin/perl
use warnings;
use strict;

my $mac_address = '28:8a:1c:59:cc:85';
$mac_address =~ tr/://d;
print join '.', unpack '(H4)*', pack 'H*', $mac_address;

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Update: Could anyone use pack to skip the colons, without the need to remove them beforehand?

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

[download]

In reply to Re: Concatenate and join by choroba
in thread Concatenate and join by Anonymous Monk

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