Just to be up-to-date …

Why we should keep attention to how we design websites with scrollbars:

  • Offer a scrollbar if a page has scrolling content. […]
  • Hide scrollbars if all content is visible. […]
  • Comply with GUI standards […]
  • Avoid horizontal scrolling on Web pages […]
  • Display all important information above the fold. […]

en detail and more to read:

Jakob Nielsen’s Alertbox : Scrolling and Scrollbars