
Lightbox effects used to implemented to overlay image, to have flash likes effect in non flash web page using javascript, but nowdays the implementation has became various can be used to overlay images, video, flash movie, dialog or alert box, even wrapping external web page and form submission collaborated with ajax method.
Here i listed some of the excellent lightbox effect libraries that you can choose to have overlay effects in your web pages.

overlay images effect made by Lokesh Dhakar, uses Prototype Framework and Scriptaculous Effects Library, Lightbox has inspired the others lightboxes.

Slimbox is a 7kb visual clone of the popular Lightbox JS v2.0 by Lokesh Dhakar, written using the ultra compact mootools framework. It was designed to be small, efficient, more convenient and 100% compatible with the original Lightbox v2.

ThickBox is a webpage UI dialog widget written in JavaScript on top of jQuery library. Its function is to show a single image, multiple images, inline content, iframed content, or content served through AJAX in a hybrid overlay modal window.

Written by Răzvan Brateş used to display remote content loaded using AJAX, web 2.0 style, written for the mootools framework. It can be used to display some help document, an extra options page, a registration form, etc.

Written by Kevin Miller one of my favourites, Lightwindow is based on Prototype Framework and Scriptaculous Effects Library, and Lightwindow can be your one stop solutions for overlaying content in your web page, can be used to overlay images, video, flash movie, inline content, external webpage, ajax form etc., but though the layout styling using CSS it is still a lil bit difficult to do the modification. Overall lightwindow is one of the best
Videobox: Lightbox for videos :

Videobox is a 6kb script, which shows your videos in the page with an overlay. It was inspired from Lightbox.v2 and uses some of the Slimbox’s code. It’s written for the wonderful mootools library. And used swfobject to embed flash. link

Facebox is a jQuery-based, Facebook-style lightbox which can display images, divs, or entire remote pages. Uses transparancy round corner style.

Lightview written by Nick Stakenburg as the site says overlay images anything with style, Lightview can be used to overlay image, set of images, external web pages, quicktime video, flash movie, ajax form, Iframe, inline content, I personally love the style, adjustable rounded corner without PNGs image, useing Prototype 1.6 Framework and Scriptaculous Effects Library.

another lightbox effect by pathfusion, it was designed to give inline popup effect to a link which were targeted to images, flash, flv (flash video), multimedia (Quicktime, Window Media, Real, mp3s), and html with ability to add ajax functionality, was made using mootools v1.11 and to embed flash object using swfobject.js.

Shadowbox is a cross-browser, cross-platform, cleanly-coded and fully-documented overlay media viewer application. Supported images, flash, multimedia, html and ajax page. Shadowbox is cross-adapter, means it was built with support to different javascript framework to run with such as: Yahoo! User Interface Library, Ext (standalone), Prototype + Scriptaculous, jQuery, MooTools.

GlassBox is a compact Javascript User Interface (UI) library, which use Prototype and Script.aculo.us for some effects. With GlassBox you can build transparent border, colorful layouts and “Flash-like” effects. I personally love the homepage, excellent effects.
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