Buy a Makita Li Ion tool kit and get a free battery by redemption.
I picked up a nice Makita impact driver from bunnings last week. It came with two 3.0ah lithium batteries, impact driver and fast charger. By redemption you get another battery the same as in the kit. This kit was $398. This battery you can get for a bit over $100 on ebay, heaps more at hardware stores.
They had another for $398 which came with the drill and the impact driver, but the batteries were only the 1.5ah ones which are probably fine for most people. You would get a free 1.5ah battery with this kit.
Great thing about these you can get angle grinders, circ saws etc that work off these batteries.
Cool stuff. Makita is pretty good.