Can you believe Hong Kong Airlines has been around for 8 years now? Happy Anniversary. To celebrate they’re offering some discounted fares for travel March 31, 2015 to October 31, 2015. Book by December 5th. (Keep in mind blackout dates.)
Fares are decent, with flights from Hanoi to HK for example for a mere $76 USD roundtrip, before taxes and fees of course. One thing weird though, I don’t see a HKG to Hanoi flight on sale.
Unfortunately, this is no where as nice as the HK Express sale a few weeks ago where fares were a mere $1, plus the travel dates were pretty much whenever you want to travel. Take a look though if you can plan in advance, something might work for you.