Figuring out cost of utilities easier with device

Every month when its time to pay my gas, electricity and water bills, I'm curious to see how much I've used my utilities and how that compares with what my household used for the same month a year ago.

I'm always looking to save money, and the usage comparison is a quick look at if we're doing anything to lessen our consumption, and thus, what we pay for utilities. Last month, for example, our home's kilowatt usage per day dropped almost three kilowatts, or 39%. That's quite a drop, but I attribute it to being out of the house on vacation for a little more than a week.