I was just looking at JTL Networks (http://jtlnet.com) and they provide a link to phpinfo() running on their site. I thought that was very clever.

Certainly a lot better than having to send off a email request asking what php modules are installed, and then waiting 14 hours for a reply listing installed apache modules.

I'd like to encourage all hosting companies with php to provide a link to a file that contains phpinfo.

<?php
phpinfo();
?>

Thats a very good idea.

Some other hosts already do this too, but you generally have to ask for it as the URL is not always posted on their website.

http://www.mchost.com/phpinfo.php

we have a phpinfo and a perldiver script on our site because we get quite a few people asking us what we have installed

Yes and I find that 99% of the time it is in the format of www.okihost.com/phpinfo.php lol.. :)