If you want to experiement with alpha in icons, the following info may be of use:
Icon Format
To author 32-bit icons correctly, do the following:
Author multiple images for each icon. The following graphic shows this.
Multiple Images of the Same Icon
In the previous graphic the first three images are in 16-color mode for use in safe mode.
The next three icons are used in Windows XP 256-color mode.
The last three icons have the alpha channel and can be used only in Windows XP or future operating systems running 24-bit color or higher.
The order of images in the icon format does matter. If the order is wrong, older versions of Windows function poorly when extracting the icons. Extracting the icons incorrectly can cause memory corruption and improper rendering.
Previous versions of Windows had a 10-icon resource limit, but Windows XP supports thousands of icon resources.
Note You can use third-party tools to generate icon files and bitmaps that contain an alpha channel.
pretty pics at http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnwxp/html/xptheming.asp
Icon Format
To author 32-bit icons correctly, do the following:
Author multiple images for each icon. The following graphic shows this.
Multiple Images of the Same Icon
In the previous graphic the first three images are in 16-color mode for use in safe mode.
The next three icons are used in Windows XP 256-color mode.
The last three icons have the alpha channel and can be used only in Windows XP or future operating systems running 24-bit color or higher.
The order of images in the icon format does matter. If the order is wrong, older versions of Windows function poorly when extracting the icons. Extracting the icons incorrectly can cause memory corruption and improper rendering.
Previous versions of Windows had a 10-icon resource limit, but Windows XP supports thousands of icon resources.
Note You can use third-party tools to generate icon files and bitmaps that contain an alpha channel.
pretty pics at http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnwxp/html/xptheming.asp