Link: https://code.launchpad.net/~edb/quam-plures/register_link_in_menu
The "menu" widget has a handful of fairly simple options, but it didn't have "register". For some reason it was assumed the potential registrant would know they had to select "login" in order to be able to register. This branch is very simple: it adds a register option to the menu widget.
UPDATE: branch merged into core on 2011-01-09. Three Cheers!
