At the supermarket I noticed 3 Watt LED replacements for MR16 halogen down lights at $AU11.99 each. These were branded "Essential", Woolworths own brand (at the supermarket in Westfield Belconnen, Canberra). Previously I tried a Mirabella brand 1 Watt 12 Volt LED Diachronic light for about AU$15, but it gave poor quality light and stopped working after a few months. The Woolworths units look a lot better made, with one LED in a substantial aluminium heat sink.
The units are claimed to be equivalent to a 20 Watt halogen unit (110 Lumen). If they last the claimed 30,000 hours, then they would be worthwhile.
There are very many 50 Watt downlights in Australian homes. If these were replaced with 3 Watt units, it would save a lot of energy and greenhouse gas emissions. This would be a more effective project for Australian Governments to subsidise, than the current solar power rebate.
Fitting these units would also reduce the prevalence of house fires caused by high wattage down lights over heating. The government might want to offer a set of these lights (and larger 240 Volt low energy florescent down lights) to all Australian householders.