First, if you are going to post in the forum please select a real name.
eZ publish does not have this kind of functionality, only a shorten operator ( http://www.ez.no/ez_publish/documentation/reference/template_operators/strings/shorten ). In order to achieve this you would need to create a custom template operator in PHP.
Even with such an operator you can not guarantee that the design won't be broken since people can override fonts and font sizes in their browser. In theory this means that the font size could be unlimited which will break any design.