A Case of Scroll Bars Bad Use
Scroll bars are use everywhere on websites, they are specially useful when the information you want to display does not fit on the browser window.
Scroll bars can also confuse users if they are not properly implemented. When making your interface design you have to keep in mind that scroll bars take space themselves and sometimes make navigation confusing.
An example of bad use of scroll bars could be found at last.fm. If you go to the Top Listeners page for a particular artist, you will get a list of users that were listening to that artist with the personal info of that people. Here you can see that scroll bars are where they are actually not needed.

This also represents a usability problem, users might get confuse and think that more information is hidden next to the people’s picture.
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Disclaimer: with this kind of article I want to point out usability and interface problems some sites could have. Please do not take this as an attack, take it as a free advice. I would like to make clear that this design problems could happen for many reasons, including lack of time or money.
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