Also check out CGI docs and search for cookies.

#!/usr/bin/perl
use CGI qw(:standard);

@ANIMALS=sort qw/lion tiger bear pig porcupine ferret zebra gnu ostric
+h
    emu moa goat weasel yak chicken sheep hyena dodo lounge-lizard
    squirrel rat mouse hedgehog racoon baboon kangaroo hippopotamus
    giraffe/;

# Recover the previous animals from the magic cookie. 
# The cookie has been formatted as an associative array 
# mapping animal name to the number of animals. 
%zoo = cookie('animals');

# Recover the new animal(s) from the parameter 'new_animal' 
@new = param('new_animals');

# If the action is 'add', then add new animals to the zoo.  Otherwise 
# delete them. 
foreach (@new) {
    if (param('action') eq 'Add') {
        $zoo{$_}++;
    } elsif (param('action') eq 'Delete') {
        $zoo{$_}-- if $zoo{$_};
        delete $zoo{$_} unless $zoo{$_};
    }
}

# Add new animals to old, and put them in a cookie 
$the_cookie = cookie(-name=>'animals',
                     -value=>\%zoo,
                     -expires=>'+1h');

# Print the header, incorporating the cookie and the expiration date..
+. 
print header(-cookie=>$the_cookie);

# Now we're ready to create our HTML page. 
print start_html('Animal crackers');

print <<EOF; 
<h1>Animal Crackers</h1> 
Choose the animals you want to add to the zoo, and click "add". 
Come back to this page any time within the next hour and the list of  
animals in the zoo will be resurrected.  You can even quit Netscape 
completely! 
<p> 
Try adding the same animal several times to the list.  Does this 
remind you vaguely of a shopping cart? 
<p> 
<em>This script only works with Netscape browsers</em> 
<p> 
<center> 
<table border> 
<tr><th>Add/Delete<th>Current Contents 
EOF
    ;

print "<tr><td>",start_form;
print scrolling_list(-name=>'new_animals',
                     -values=>[@ANIMALS],
                     -multiple=>1,
                     -override=>1,
                     -size=>10),"<br>";
print submit(-name=>'action',-value=>'Delete'),
    submit(-name=>'action',-value=>'Add');
print end_form;

print "<td>";
if (%zoo) {                     # make a table 
    print "<ul>\n";
    foreach (sort keys %zoo) {
        print "<li>$zoo{$_} $_\n";
    }
    print "</ul>\n";
} else {
    print "<strong>The zoo is empty.</strong>\n";
}
print "</table></center>";

print <<EOF; 
<hr> 
<ADDRESS>Lincoln D. Stein</ADDRESS><BR> 
<A HREF="./">More Examples</A> 
EOF
    ;
print end_html;
[download]

That is precisely what I am trying to do... But the questions still are: Is this the best way to do it? And wouldn't it require that I create all the ADD page code on the fly?

Is it the best way? How else are you going to do it? Some would say it's better to keep the info in a database, because some people don't allow cookies, and it prevents cookie tampering, but for a chatroom, maybe it dosn't matter? Of course you will have to create all the pages on the fly, but that is what cgi is all about. You can greatly reduce the amount of work the cgi has to do, by making pre-made templates of pages, and just adding the custom cookie data to it. Most monks recommend Html::Template, but for simple pages, you can put the html in "here docs" and just fill in the $username and $city variables "on the fly". There are plenty of here-doc examples around.

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I'm not really a human, but I play one on earth. flash japh