interoperability between git and other VCS and data storage/transfer tools?

Hi all,

[Please CC me in reply, I am not subscribed]

I would like to be only using git on my local systems but there are other folks out there who prefer to use different VCS systems.

In addition there are VCS-like data storage systems (such as Mediawiki) and general data storage/transfer systems where one might want to track changes using git (such as LDAP and rsync).

I still need mostly bi-directional interoperability between git and CVS, Subversion, Mercurial, Breezy/Bazaar, Darcs, Mediawiki and rsync. On the horizon are Fossil and Pijul but I probably won't need those any time soon. Recently I had a situation where GNU Arch support would have been helpful for viewing historical commit information but I assumed that support for it didn't exist so I didn't bother.

Is there a location in the git documentation for pointers to software (such as git-remote-* helpers) that can help with VCS interoperability?

Is there a place for people interested in VCS interoperability software to collaboratively maintain them?

Should the VCS interop software in the git git repo move there?

I'm currently using the following tools:

CVS: https://github.com/osamuaoki/git-cvs (slightly better than git-cvsimport)
Subversion: git-svn (not using a git-remote-* workflow)
Mercurial: git-remote-hg (there are lots of forks/implementations)
Breezy/Bazaar: git-remote-bzr (there are lots of forks)
Darcs: nothing as only fast-export/fast-import seems possible
Mediawiki: https://github.com/Git-Mediawiki/Git-Mediawiki
rsync: manually rsyncing and importing commits

What other tools are folks using?

Any other thoughts on this?