Many websites now attempt to figure out what you are trying to look for even before you are done typing! This technique is called auto-complete and uses AJAX (Asynchronous JavaScript and XML) to retrieve the closest matched, highest-ranked results from a database every time you hit a new key on the keyboard. What sites use this, and how does it impact the usability of the site? Does it add value and for whom? What are Captchas, which sites use them, and how do they work for visually-impaired users?