It's surprising what you can do with an Arduino and the right parts, and this has been demonstrated quite well by the people at Adpslab with their demonstration of the TI INA209 current/power monitor IC. It's easy to use with an Arduino due to the I2C interface, and with the demonstration circuit you can measure current, voltage, power and also note peaks and other anomalies of measured data. The results are shown on an LCD and with a little effort the whole lot could be mounted nicely in an enclosure. Here's a quick demonstration of the unit at work
That's a useful device and also an interesting example of home-made test equipment and I2C bus use, so for complete details visit the project website. And for more, we're on twitter and Google+, so follow us for news and product updates as well.
If you'd like to learn about Arduino - but not sure how to start - then the best way to learn is with our Experimenter's Kit for Arduino:
The package includes a wide variety of parts, sensors and modules including: a servo motor, lights, buttons, switches, sound, sensors, breadboard, wires and more. Furthermore a Freetronics Eleven Arduino-compatible board is included to make this an extensive hobby experimenter, inventor and starter kit. However we don't leave you alone to figure it all out, included is a great project and instruction booklet, plus access to a supporting web page and software examples. In other words - this is everything you need to get started for a fun range of electronics and Arduino related projects!
So to get started or for more information and to order, check out the product page.