AJAX put to good, simple use

One of the most simple uses for AJAX is to monitor form input and then let the user know whether what they've entered is likely to be acceptable/available (e.g. choosing a username at signup). Even so, there are ways to do it well and I just found one. I followed a link from the news on Vitamin to the new JPG Magazine site. It's not a magazine I'd read in the past, but it looked quite cool with some good photography so I went to sign up on the site to check it out more. The sign-up form is kept simple, to the point and with a helpful login form to one side in case you're already a member and just a bit confused to end up at the sign-up page. Start filling in the form and the AJAX kicks in: enter your email address and once you move focus out of the email input, a little green tick in a starburst appears alongside with the text "It's cool". Make your way through the rest of the short form and there are a couple more friendly messages to let you know you're on the right track. Get it wrong and you're provided hints on fixing the problem. None of this is hugely new, indeed I've used it on sites for quite a while, but I felt JPG Magazine did it particularly well in combination with the simplicity of the rest of the form, so kudos to 'em.