Two or three times over the past six months or so of daily usage of my Lenovo (IBM) Thinkpad T60 laptop  I've encountered an issue where the system seems to get stuck in a "always scrolling down" state: in the active/foreground application  if the application has a vertical scroll bar  the document automatically scrolls to the bottom  even though I'm not touching the mouse wheel or otherwise doing anything that would cause the document to scroll