Enter BatteryBar, a free, easy, and so-smart-it-should-be-built-in power gauge that's compatible with XP, Vista, and Windows 7.
On most systems, you have to mouse over the tiny System Tray power icon to get Windows' read on how much battery life is left. BatteryBar adds a full-time, at-a-glance gauge to the right side of the taskbar, which by itself is handy.
Mouse over the gauge, however, and you get a wealth of additional information, including total battery capacity, charge/discharge rate, AC status, and even a lifetime estimate based on historical charge/discharge data. Take a look:
I'm convinced: BatteryBar is a must-have utility for mobile workers. Even better is the Pro version, which adds worthwhile features like low/critical battery warnings, custom themes, and the option to choose a Windows power scheme.
Interestingly, the developer lets you choose your own price (sort of) for BatteryBar Pro: $6-10 for a lifetime license, $4-5 for a two-year license, or $1-3 for one year. While I think most users will be happy enough with the free version, I really like this approach -- and I suspect I'll take advantage of it.
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