linux.conf.au
Various linuxconf galleries; linux.conf.au is one of the major Linux conferences and regularly attracts superb speakers from around the world. Organised annually under the aegis of Linux Australia it takes place in a different Australasian city every year.
I'm fortunate enough to have been able to attended every conference from 2012 on, as well as the Wellington 2010 conference (in no small part due to my employer being prepared to cover my costs).