Why does my Web browser display some book-marked sites with a custom icon?
The first thing you need to do is come up with a suitable icon. Icons are just simple 16 by 16 pixel bitmap images, but Explorer won’t use ordinary GIF or JPEG files. You’ll have to save the image as an ICO file, a special icon file format. The biggest difference between this format and GIF and JPEG files is that ICO is designed to save multiple sizes and color schemes of one image. This is because Windows displays desktop icons in a variety of ways depending on the context and monitor settings. It’s not very difficult to create an ICO file; this site has online programs that will convert your bitmap image to the ICO format or let you generate a new image in ICO format. It also has a free downloadable trial version of a converter program, with instructions of how to create your graphic. As a general note, if you are creating custom icons in any format, design them as 16 by 16 pixel
