Basically, you need to register (free) for IKEA family from in-store, or online here: https://secure.ikea.com/ms/en_AU/secure/family/index.html
After registering, you can print out a temporary card, which can be used for their discounts. I registered in store and it printed out a temporary barcode for me.
After the discount, the 4xAA/AAA charger is only $15, which is a steal, considering it's a fast (2.5 hour) smart charger with four individual charging channels.
Charger: http://www.ikea.com/au/en/catalog/products/40241314/
Review: http://lygte-info.dk/review/Review%20Charger%20Ikea%20Ladda%...
The charger will work well with eneloops, the Ikea batteries mentioned below, or any other Ni-MH batteries.
4xAA batteries : http://www.ikea.com/au/en/catalog/products/00240585/
4xAAA batteries: http://www.ikea.com/au/en/catalog/products/30240584/
These batteries are ofcourse rechargeable, and are LSD. They've been tested by people at BLF and CPF, and they're pretty decent in terms of cycles (similar to chinese Eneloops), and capacity. Their LSD is abit inferior to Eneloops, so if you're going to be charging them once 1-2 years, you may consider Eneloops.