Windows taskbar button widths

How can I change the Taskbar Button widths in Windows systems (esp. for XP and Vista)? I like to make the buttons narrower so that I can see only the icon of the related application window. Is it possible for all versions of Windows operating systems?

[Update: www.kellys-korner-xp.com/xp_tweaks.htm stands broken at this time -- I've 'unplugged' the links to be safe]

At this Registry Edits for Windows XP "Tweaks and Tips" site XP page(www.kellys-korner-xp.com/xp_tweaks.htm),
There are two VB Scripts to tweak the size (besides a lot of other tweaks).

Its VB Script, so you can download it, look at it, change it -- have fun.
^{Not sure if it will work for Vista too.}

VBScript refs: Decrease the Size of Taskbar Buttons(www.kellys-korner-xp.com/regs_edits/taskbaricons.vbs ) and Undo(www.kellys-korner-xp.com/regs_edits/taskbariconsundo.vbs).

There is also a Windows 7 reference.