Get Vista Taskbar Thumbnail Previews in Windows XP
It was only a matter of time before people started cloning Windows Vista features and adding them into Windows XP. One of my favorite Vista features is the thumbnails that popup when you mouse over the taskbar. And now I can use them in XP as well.
The utility we’ll use is called Visual Tooltip, which is a hybrid dock / thumbnail applicaton. With a few tweaks to the settings, we can make it work just like Vista thumbnails.
Source: the How-To Geek