If this had an ajax VNC-like interface as well it would be very interesting but on its own it is just a simple admin tool where they have used JavaScript to imitate the native app.
StackVM (http://stackvm.com/) by pkrumins is much more interesting as a project.
They didn't write the "detached" console functionality- They're using Sun's flash RDP client. It's a nice piece of tech, but it's licensed under the same license as the rest of Virtual Box, the Personal-Use Evaluation License.
That means it's fine for test and home projects, but you can't base a product on it.
The Virtualbox PUEL license allows commercial use as long as it's only being used by one person. And that person has to actually install it themselves.
No good for many scenarios, but we use it at work under this clause.
It is possible to purchase a license as well, although I don't think there's a public price and I dread to think what Oracle want to charge
I'm trying to find out if we are already a Oracle enterprise customer if this is covered or not. Is that something general knowledge or do I have to contact an Oracle rep?
It's more a replacement for VMWare Server than VMWare ESX.
I think KVM/Xen are closer to ESX. VirtualBox ships with a webservice that you can write custom front-ends against (or script against).
Most of the VM tools seems to miss an ability to branch a VM (i.e. take a snapshot and break it off as a seperate instance). This would be hugely useful for installer testing.
We use X11 forwarding to get this interface on our local machines with little fuss. Of course, you still have to log into the box via ssh to run the client, but that doesn't seem too onerous.
Random? This is a one-of-a-kind (AFAIK) tool for managing VirtualBox over the web. The fact that it is PHP is less important than that it exists at all and will be useful to many people who manage VirtualBox running on a server without a GUI.
StackVM (http://stackvm.com/) by pkrumins is much more interesting as a project.
EDIT: Just noticed that they do seem to have something they are calling a "detached" console. http://phpvirtualbox.googlecode.com/svn/wiki/images/phpvb8.p...
My apologies for saying its not interesting, it now is.