I've installed a redbrick-wide hgwebdir instance: hg.redbrick.dcu.ie
It's publically readable, so not really suitable for things you don't want people to see the source for, but useful if anyone's doing any open source work.
Push access is restricted to SSL (https://hg.redbrick.dcu.ie/reponame/,
which is protected by
mod_authnz_ldap (Pubcookie + hg is a world of pain). Each repository has
it's own list of which authenticated users may push (write) to it.
If any users ask for a repository, running
/srv/admin/scripts/add_hg_repo.sh on murphy will
create it for you. Repositories are in
/storage/hg and need to be owned by
function (the script does this for you). The script is interactive.