This function takes text and, after a certain number of characters have been shown, it replaces the remaining text with " ...". It is easily customizable.

If you didn't understand what I just said, here's the function's code and an example:
PHP Code:
function preView($variable$maxchars)
$dnum intval($maxchars);
strlen($variable) > $dnum)
$splitpnt strpos($variable," ",$dnum);
$var substr($variable0$splitpnt);
$var .= " ...";
strlen($variable) < $dnum)
$var $variable;

Example and Output:
PHP Code:
$variable 'This is so cool!';
$new_variable preView($variable5); 
That would output 'This ...' (quotes excluded) because it goes five characters before it dots the rest.

Disclaimer: I found this script somewhere else, renamed the function, and some of the variables names are changed.