You can adapt the code from perlfaq5 (and, like it says, the Camel book) How do I select a random line from a file? for when iterating through your hash, once, instead of through the lines of a file. 
my $chosen;
my $n = 0;
while(my($k, $v) = each %hash) {
    rand(++$n) < 1 and $chosen = $v;
}
return $chosen;

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In reply to Re: Random hash element (low memory edition). by bart
in thread Random hash element (low memory edition). by amarquis

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