use List::Aged;
my $list=List::Aged->new();
$list->add( -expires => "60 seconds", "some","list",
       "of","random","stuff");
$list->add( -expires => "10 hours", "whee");
$list->exists("random"); # true, for now
sleep(61);
$list->exists("random"); # false now
$list->exists("whee"); # true