These two are cheapest Portable 2.5" HDD out in New Zealand retail store at the moment, so will be good for those who needs some external storage space and aren't buying them from overseas. Checked via PriceSpy
Seagate 2TB Expansion Portable 3.0 Hard Drive $129.99 - ~0.065$/Gb (Noel Leeming is also selling this for the same price, so get it from NL for 5 Flybuys point)
Imation 1TB Portable USB 3.0 Hard Drive $78.00 - ~0.078$/Gb
Offer expires on 1st June