In Canberra, I like Au Lac - a vegan Vietnamese restaurant in Dickson.
In Sydney I am still trying all the options, but I have a fondness for Bodhi (in Cook & Philip Park) and Iku.
There is also a great vegan thai restaurant in the CBD - Fresh & Healthy or something?
I also love the black sesame 'ice cream' at Green Gourmet in Newtown, but don't always find their meals to be the best value.