[openbox] How to bind the Super key (just the super key)?

[seanh]

Hey, in Ubuntu's Unity I just tap the Windows key to activate the dash.
I think Gnome 3 does something similar, too.

Is it possible to bind just tapping the Windows key alone in openbox?

Currently I have:

    <keybind key="W-Return">

but if I try to change it to something like:

    <keybind key="W">
    <keybind key="W-">
    etc

nothing seems to work.

Unity can also distinguish between a tap of a key and a press and hold
of a key, which I don't think openbox can do either, unless there's some
hotkey manager that can be used with openbox?

Thanks