Solution for offsite backup

Hello folks,

our company needs some kind of an offsite backup.
Servers to backup are an Exchange2000 server and a W2000 file server.

The replication doesn't have to be performed immediately. If data is been
synchronized on an (two)hourly basis this would be ok. The solution also
has to be somewhat low cost. It is not neccessary that an entire mirrored
server is placed at the remote location. Important is that data is saved
at the remote location to prevent a complete loss of data in case of e.g.
fire or burglary.

So I set up a Linux server at the remote location and I synchronize the
data on the file server via rsync. The data is then written to tape on a
daily basis (a far more advanced scenario would be to commit the changes
in synchronized data into a versioning control system like cvs or
subversion, providing some archiving features as well, but that will
increase the amount of data considerably). Works fine and the type of the
Internet connection needed of cause depends on the amount of data that
changes during the day.

But this concept doesnt apply for the exchange server with its huge
proprietary databases.

And here is my question:
Which solutions are known to backup the exchange data over a rather slow
connection?
I know of some expensive products that claim to mirror entire
servers between remote locations, but I do not trust them until I have
recommendations from actual users.
Any tips are greatly appreciated, whether they imply self made solutions or
a commercial product.

--
mit freundlichen Grüßen
Dirk Taggesell