FogBugz Software maintains offsite backups of your Kiln On Demand account. If you wish, you can also maintain your own offsite backups of your repositories.
NOTE: We have not tested any of the scripts mentioned below with kbfiles or largefiles. Using these extension causes certain versions of files to only be retrieved from the server when you update to a given revision. Some versions of Mercurial will also grab every version of the kbfile/largefile when you run “hg verify”.
There are a couple of options to create off-site backups of your repositories. Essentially the core concept is to run a script on a remote server, use the Kiln API to enumerate the repositories on the kiln server and then use simple hg clone / pull commands to get current copies of the repositories on the remote server.
There are a couple of user-written scripts that do just that. The first was written by Stefan Rusek. The second was originally written by Nate Silva and is now maintained by Ken Morse, and can be found here.
These scripts are both pretty generic and might work perfectly for your needs without modification. Alternatively, you could use them as a starting point and expand the scripts to suit your own environment.