Battery Guru will place a number in your menu bar that is constantly reading and updating the current power output (or input) of your battery.

Battery Guru is simple. It shows you a number in your menu bar. This number is the measure of electrical current that is currently flowing out of your battery. As mentioned, high CPU usage can cause this number to increase wildly. Another thing that can make it increase are if your discrete graphics chip kicks in to process intensive graphics, or perhaps unnecessarily because it thinks it should be processing intense graphics but really it’s just a tiny animation somewhere that you don’t even notice.

From the moment where you install Battery Guru you will start to become vaguely conscious of this number in your menu bar, much like you’re vaguely aware of the hour most of the time. You will see if this number massively spikes, and you will correlate it with a change on your system. Much of the time will then probably decide that you don’t in fact need to have that web page open that’s decreasing your current battery usage to 20% of what it would otherwise be, and close it. This is the peaceful way of getting a lot more life out of your battery on an every day basis.

Requirements:
OS X 10.6+
64-bit Intel