Ever discovered an exciting new feature about your Mac, only to realize later that you were the last person on the planet to know about it? If you want to reign as the King of Macs, you must know every detail.

This series will highlight the under-discussed and oft-overlooked features of Apple hardware and software with the hope of bringing something new to all those Old Dogs out there.

First Up: The Secret Battery Meter

Although this feature is clearly documented in the manuals for Apple portables, many recent switchers and even seasoned veterans of the Mac world have never seen it. Part of the problem may be that it is on the bottom of the machine, certainly an unglamorous area.

Those who own only one battery, or missed out on the recall fun, have little reason to turn their laptops over. Unless you have some other excuse to engage in Mac flippery, this feature has been hiding where the sun don’t shine and you’ve never seen it! There is a meter built into every battery that Apple makes, dating back at least to the “Wallstreet” Powerbook G3. To find yours, look for a small button next to a row of dots:

This is where the real fun begins. Press the button and the dots light up to indicate the charge level in the battery. Maybe not essential for the average user, but for those obsessive types who travel everywhere with a Macbook (Pro) and a spare battery, this can be a lifesaver.

It gets better:

• Do it anytime, with the battery in or out, computer on or off.
• A blinking light indicates the battery is dead, and the computer will not have enough power to boot.
• While the battery is in and the computer is connected to it’s charger, the lights will blink to indicate the charge level.

There you have it! Another example of superior Apple design. Even if you already knew about the Battery Level Indicator, this should serve as a reminder to go and ask your friends if they do. You have a good shot at blowing someone’s mind.