Scriptaculous Autocomplete
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An Ajax autosuggest script is supposed to help the visitor and present in real time (as they type) some possible results based on their entered words/characters.
In my opinion, this is a great feature to enhance the user experience.
It's very easy to build an autocomplete form using scriptaculous and prototype.
You just need one line of javascript
new Ajax.Autocompleter(id_of_text_field, id_of_div_to_populate, url, options);
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