This came up on my Facebook feed today, Meridian and Qantas Frequent Flyer have teamed up to give 10k QFF points on signing with Meridian Energy.
Not a bad deal if you are an avid collector of QFF or fly Qantas regularly, but I couldn't seem to find their actual rate they charge - I'm currently with Mercury and will switch as soon as I can confirm what rate Meridian charge.
I believe that you could you Consumer's PowerSwitch to calculate your saving/increases in costs.