Well, I'm from Canberra so obviously the Brumbies.
But, the Brumbies have also been the best, and most exciting Australian team since the game went professional.
They have an excellent development program and have turned so many players into Wallabies.
Many of the best Wallabies in recent years have come from the Brumbies (or at least made a name for themselves at the Brumbies before moving on) - Gregan, Larkham, Roff, Paul, Giffin, George Smith, Mat Giteau, Stirling Mortlock, Owen Finegan, Justin Harrison, Dan Vickerman, Rod Kafer... the list goes on...
The 2004 team was probably my favourite because they were able to demolish so many teams (including the Crusaders in the final) with such great attacking rugby and score some AMAZING tries, as well as blood so many new Wallabies that year - Henderson, Chisholm, Samo, Rathbone, Gerrard....