It is a freeware and will remain so.

Installation:
Just delete the old ArielBatteryX.exe and replace it with the new one.

Main features:
- Makes good use of the unused space of the "Start" button icon.
- Battery power is always visible, because it is on the taskbar.
- Very low CPU consumption (Only about 0.001% !!! Much less than any other battery monitoring program !!!)
- Tiny memory usage, Much smaller than kBattery, pBar, magicbutton, batmon or xbutton.
- Just put it on StartUp folder or link to it, and it will do the job!
- WM2003, WM2005 (WM5) , WM6 (Now fully compatible).
- Full control of all displayed colors.
- The gauge can be moved to replace any icon on the taskbar.
- VGA screens are supported.
- Landscape mode is supported.
- HTC Diamond supported.

Update Description:
v2.1:
- Ariel Battery Icon can now be alligned to both right and left, to support people who frequently change from portrait mode to landscape, and chose to put the icon on top of some other icon, and not the start icon. - Performance improvement.

v2.0:
- WM6 gradient color compatibility.
- Full control of all displayed colors.

v1.6.2 (31-01-2008):
- Color bug fixed.

v1.6:
- VGA screens are now supported!

v1.5:
- Landscape mode is now supported!

v1.4:
-The battery icon can be moved to replace other icons on taskbar.

***** [Jan 15, 2009] by JT using Samsung Omnia
I noticed that the latest version only display the power % in tens ie. 90%, 80%, 70% while it used to be able to show the actual percentage eg. 97%, 85%, 73% etc.

**** [Feb 25, 2008] by hierophant using Acer n310
Neat little utility, unobtrusive yet always available. You don't have to have it on the start button, I moved it to the right next to the speaker icon. Perhaps it's not an essential utility, but it's very reassuring.

**** [Feb 19, 2008] by accho using HTC Touch Upgraded
Nice! Could the size of icon reduced to half so that part of the Start ICON remains accessable e.g. removed the words & leave a small icon.