This has been around for a while but I just realised it hasn''t been published... http://xenbits.xen.org/git-mapfile.gz maps Mercurial IDs to git IDs up to the point where we switched from mercuial to git. The left column is the git ID and the right column is the mercurial ID. Hopefully this is useful if you are looking at old bug reports, test results etc which contain hg ids and want to stay in the git world. Note that the mapping stops when we switched to git, so there is no mapping from new git commits to the mercurial mirror. Sorry. Ian.