I have the new Kill-a-Watt version that lets you input your KwH rate and it will tell you how much you are paying to run that equipment for 1 day, 1 week, 1 month, 1 year and so on.. here are my findings:
Based on my rate of $0.11 per kwh, I pay:
$3.00 /mo for my Eheim 1260 return that runs 24/7............
$10.00 /mo for two 250-watt Halides............
$5.00 /mo for the wavemaker and other pumps...........
and about $15 for other stuff... like dosers, controllers, and other monitors..
I didn't include the chiller and heater since they can't be measured on a regular basis...like I don't know when they will turn ON, etc.
That being said, my entire tank costs about $30 a month to run. (and this is an SPS system with 600 watts of lighting) On the other hand, I measured my 42" plasma and it costs about $15 /mo if operated continuously!!!!
So I guess if people are having high electric bills I suggest they look somewhere and stop blaming the tank...
lol 
