HTML (ajax) Chat. Can be set up and run by anybody with a good understanding of PHP and mySQL. An alternative1: Linuxuser.at - Simple Ajax Chat; alternative 2: Ajaxdaddy.com - Jquery shoutbox; Linuxuser.at - Most Simple Ajax Chat Room.

AjaxIM is an asynchronous javascript and xml instant messenger.

A magnetic board which automatically updates the co-ordinates of a 'word square'.

A great list of nicely scripted AJAX widgets all under one roof. AJAX poller; AJAX client lookup; dragable RSS boxes ; RSS scroller ; Ajax dynamic list; Ajax tooltip & fly to basket .

This employs a similar method to the GMail file upload, using a hidden IFRAME to post the file and AJAX to check the progress. There is a tester script and instructions with the download. See also: Webtoolkit.info - Ajax file uploader and Webdice.org - Uber uploader.

Swf meets Ajax for beautiful uploads a MooTools upload widget thats allows queued multiple-file upload including progress bars.

This Multiple CSS/AJAX rater is great. The markup for any star rating component is a very simple 'PHP require' with a unique ID. It automatically creates an entry in the MySQL table whenever anyone votes.

Unobtrusive Degradable Ajax Style Sheet Switcher. Page style choice is retained on page load using server-side cookies.

A poll script using Ajax to send your vote to the serverand to return the results from the poll to your browser. The number of votes per user can be limited by setting the Javascript variable useCookiesToRememberCastedVotes to true in the script. An alternative: Andreashuebner.com - Andypoll.

MODx is an open source Ajax CMS and PHP Application Framework.

Tiddlywiki.com - AJAX WikiA free MicroContent WikiWikiWeb. Create your own WIki site in an instant.

An AJAX edit-in-place app. Demonstrates how to do a simple AJAX call with prototype.

AJAX edit text in place using xmlHttpRequest.

Javascript reads all SPAN tags for class="editText", adds a onclick function which creates a textfield or input (depending on the size of the editable text). Someone has the ability to edit the field. When the text field is blurred, it will read the contents, and starts a XMLHttpRequest and ‘sends’ the content + fieldname + any set vars to an update file. That file will update your database, and reply with the newly set text and the textfield will dissapear again.

Create flickr-like Editing Fields Using AJAX & CSS.