CITY MAIL appears over the weekend: But what is it?

Over the weekend, a strange box has appeared attached to a telephone pole near The Coast's office, at the corner of Cunard and Creighton Streets: Upon further inspection, the box has this note attached to it: The note reads:

It is easy to write your city
with CITY MAIL

CITY MAIL is an initiative dedicated
to the delivery of inner-city
postables, in Halifax.

To send mail with CITY MAIL
simply indicate the address
(to the best of your knowledge)
on your envelope/package.

No postage requred--
CITY MAIL is free-mail.

Mail boxes will be emptied,
Their contents, distributed,
on a minimum-weekly basis

**CITY MAIL is pleased to
announce the expansion of
our service, to the city of
Montreal. You are welcome to
send free mail via CITY MAIL
in these boxes.
remember to indicate the
city and addresss, intended.

This is quite an undertaking. I wonder: Who's behind it? Do they have permission to attach boxes to poles? Is there a particular beef with Canada Post, or is it an anarchic attempt to build a different form of mail system? What's up, anyway?

If anyone knows anything, I'd appreciate some info coming my way.