What is 7stacks?
7stacks is an easy to use, free app that lets Windows 7 (and Vista and XP) users have "stacks" of icons in their Taskbar (in 7) or QuickLaunch Toolbar (in Vista and XP). By using stacks, users can reduce icon clutter, and combine a group of related icons into a single icon. For instance, if you use application suites such as Microsoft Office, OpenOffice, or Adobe CS4, you can have all the suites icons combined into one icon!
The program seems to be no longer updated. Last version, v1.5 beta 2, released on June 27, 2011, can be still downloaded from the official website.