This package adds an element to the PEAR::HTML_QuickForm package to dynamically
create an HTML input text element that at every keypressed javascript event,
returns a list of options in a dynamic dropdown select box
(live dropdown select). This element use AJAX (Communication from JavaScript
to your browser without reloading the page).
This type of livesearch is useful when you have a form with a dropdown list
with a large number of row.

WWW: http://pear.php.net/package/HTML_QuickForm_Livesearch/