If there's some character you can guarantee is not in the strings (so that you can use as a separator — I chose space), you could do 
my @common = (join ' ', @s) =~ /(.)(?=(?:.* .*\1){$#s})/g;

[download]
Not really elegant; I just thought it was a nifty one-liner.
Caution: Contents may have been coded under pressure.

In reply to Re: Find characters in ALL strings by Roy Johnson
in thread Find characters in ALL strings by Anonymous Monk

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