Basically, I think that I can't, but I would be very happy to be proven wrong.
I am generating an HTML menu dynamically in PHP, adding one item for each current user, so that I get something like
<a href="process_user.php?user=<user>>, but I have a preference for POST over GET.
Is there a way to pass the information as a POST parameter, rather than GET from a clickable HREF link?
It looks like Rob is on to something with "You could use a button instead of an anchor and just style the button to look like a link. That way you could have your values in hidden fields inside the same form to be sent via POST"