I just had the opportunity through work to go to NDCSydney and have only 1 word to summarise it: BRILLIANT, Great speakers including:

Lynn Langit
Scott Hanselman
Rachel Reese
Jon Skeet
Joe Albahari
Sabine Bernecker-Bendixen
K Scott Allen
Sam Newman
Troy Hunt
Kylie Hunt
Adam Coogan
Alex Mackey*
Shawn Widermuth
John Galloway
Damien Edwards
and lots lots more

*fellow Xero person

Brilliantly run conference and I was lucky to attend a 2 day workshop on ASP.NET core run by Damien, John and Hanselman.