Flexselect is a jQuery plugin that turns regular select boxes into Quicksilver-like, flex-matching, incremental-finding controls.
Select or Die is a jQuery plugin to style/replace
Selectonic is a jQuery based plugin for making any list of items selectable by mouse and keyboard. It could be usefull in web app where are different widgets like menus, dropdowns with keyboard input, lists with multiple selection and so on.
EasyDropDown is a jQuery plugin that effortlessly turns humble
<select> elements into styleable drop-down menus for use in forms or general UI/navigation.
gentleSelect is a jQuery plugin for transforming select boxes into a skinnable alternative. The selection list can be rendered with multiple columns/rows to present larger datasets in a more manageable format. It recognizes the multiple attribute on select boxes and does the right thing automatically.
FancySelect is a better select for discerning web developers everywhere and it is easy to use.
HeapBox is plugin for jQuery that replace native HTML selectboxes in your webpages. HeapBox supports themes, events, callbacks, ajax and much more.
Chained is simple jQuery plugin for chained selects. There are two different versions.
A simple and lighweight jQuery plugin for cascading dropdowns.
The plugin allows you to implement a cascading dropdown using multiple select boxes in which one select box depends on the input from one or more separate select boxes. Once one or all (depending on the configuration) required select boxes contain a value, it will trigger an event that will fire off the dependant select box so it will fetch its own list.
Selectize is a jQuery-based custom
<select> UI control. It's useful for tagging, contact lists, country selectors, and so on. It clocks in at around ~7kb (gzipped). The goal is to provide a solid & usable user-experience with a clean and powerful API.
Minimalect is a jQuery plugin for minimal and custom select replacement.
Multiple select is a jQuery plugin to select multiple elements with checkboxes. Multiple Select supports methods that allow programmatic control of the component.