Well, I love graphs, they are the bast way representing data for me and this sounds like a good project.
I got myself over to eco gadget shop and bought one. It was dead easy to install, and I started keeping track of how much electricity I was using. What was a "good" amount, and what wasn't.
There are two parts to the device, a balck box "transmitter" that you put in the cupboard with your meter and
The receiver is about 6 inches high, and has an LCD display, and is claimed to use 1.8W to run, which is nice and small, considering that these things are sold as a way of cutting down on your electricity usage. It also has a serial port on the bottom, which is how everyone gets the data from it.
Unfortunately this serial port is a) RJ45, and b) TTL level, which means that iyou can't just wire it up to a normal serial port without a bit of work. There are instructions for making a cable, complete with a circuit diagram containing a max3232 available, or there are reports of being able to buy a cable from the manufacturers
Alternatively you can do what I did, and "cheat".
Last updated: 18:28, 30 Aug 2008 Link..