In the Gnome Git documents, there is a little gem hidden which deserves to be repeated:
Since all gnome modules have a common url prefix, it can be convenient to set up a clone alias:
git config --global url.ssh://[login]@git.gnome.org/git/.insteadof gnome:Then the clone line becomes much shorter:
git clone gnome:[project]
Don’t forget to change [login] and [project] to the appropriate values in the above.

Great tip, thanks!
Maybe avoid an accidental push (nah, no idea how that could happen), one could use
git config –global url.git://git.gnome.org/.insteadof gnome:
this way you get access to the read only version
Also to my big surprise i found out how good the tab-autocompletition in command line works – try it out!
Thanks for this tip, really helpful :]