?

What is this box?

A bloke came and attached this box to the lamp-post opposite work last week:

(ignore the hula-hoop - that's been there a couple of weeks. Nice shot, BTW!)

Another angle:

So - what is it? Theories to mysterybox(at)chthonic.f9.co.uk

Possibilities so far...

Key storage
Why angle it down with a special mount? Not exactly secure...
Traffic/iBus monitor
Not a bus route. Surely the metal box somewhat gets in the way of any sensors?
Tinfoil hat dispenser
Could be..

Update 1

The public lighting sign at the bottom of the second photo says the lamp-post is "under repair" and that has been there even longer than the hula-hoop. Westminster like to leave their signs around till they mature - up the street there's one celebrating "Colour in East Marlebone 1992-1993"

Update 2

More suggestions

Speed survey thingy
I don't think so purely because it's got a metal front door and lock that would get in the way. Plus it's a wiggle side street and mounted by the world's worst pothole, making it really hard to do more than 20mph, even on a bicycle.
A noise monitor
More likely - but still no aerial for a wireless data connection (unless it's a small stub on the top, out of sight). Still, could be recording for later use.
A pollution survey at Imperial College
Possible. I've emailed one of the people involved. NOPE - "
Its not one of mine - sorry. The mystery continues!
"
A TARDIS
..because they are bigger on the inside
The world's worst bird box
YES! FOLKS WE HAVE THE ANSWER

Update 3

Oh my god... it's full of stars