
Since the Argo project works via a simple network protocol you are free to write, or use, a client upon any machine upon your LAN.
There are several clients distributed with the downloaded package:
(Note: If you write your own client I'd be happy to either host it here, or add a link to it.)
The Perl + Gtk client should be installed if you install the source tarball, or once you install the argo-client-perl binary package.
Once installed you can launch the client by running "argo-perl".
Once the client has been loaded you may use the "File | Connect" menu item to enter the details of the server you wish to connect to.
The list of available instances should appear in the treeview on the left. Selecting an instance will fill the list towards the right with the details of that instance.
Once an entry has been selected the "stop", "pause", etc. buttons will work as expected.
Here is the obligatory screenshot:

Once you've installed from source, or via the argo-client-php binary package for Debian, you should have some PHP files located in the directory /usr/share/argo.
You should setup your Apache server to load these, perhaps via a virtualhost such as this:
<VirtualHost *>
DocumentRoot /usr/share/argo/
ServerName xen
ServerAlias xen.my.flat
DirectoryIndex index.php
# Logfiles
ErrorLog /var/log/apache2/xen.log
CustomLog /var/log/apache2/xen.log combined
</VirtualHost>
Once the virtualhost has been setup you can point a web browser at the index.php page.
As a simple console-based client the Debian binary package argo-client-dialog contains a client which can be used via the console.
It is written in the bash shell, making use of netcat to make socket connections and the dialog tool to display a simple GUI.
The Dialog client has its own page of screenshots
Development upon argo has ceased pending a redesign.