EEPROM is a useful type of memory, you can store and retrieve bytes of data very easily and there's some included in the microcontroller used in all Arduino and compatible boards. It's reliable, easy to code for and great for storing settings or other data. However if you choose to use EEPROM for logging data, you might run out quickly. The people behind the heliosoph website had the same problem and solved it by using banks of external EEPROM ICs interfaced with the I2C bus.
To help others they have documented this process, including not only the required parts, but also some interesting discussion about using the I2C bus and also logging the captured data with time using a real-time clock IC. With their clear tutorial, you'll be using this new form of storage in no time - so visit the project page to learn how. And for more, we're on twitter and Google+, so follow us for news and product updates as well.
If you're looking to learn about Arduino and EEPROM or just how to get more from your Arduino or compatible board, you can't go past "Arduino Workshop - A Hands-On Introduction with 65 Projects” by John Boxall.
Arduino Workshop takes the reader from having zero knowledge about the Arduino platform, electronics and programming and leaves them with the know-how and instructions on everything from blinking an LED, to robotics, wireless data, cellular communications, motor control, sensors, Internet connected systems and more. For more information including a sample chapter and table of contents, visit the book page.