At my highschool, they had bells for a while, but after they changed to some annoying beeping [img]/xxx.gif[/img][img]/xxx.gif[/img][img]/xxx.gif[/img][img]/xxx.gif[/img] that would beep like every one and a half seconds for about ten seconds or so. It was pure [img]/xxx.gif[/img][img]/xxx.gif[/img][img]/xxx.gif[/img][img]/xxx.gif[/img], so they changed to bells again.