A really slick looking theme for jQuery Mobile that’s very flat (no shadows etc).
#ui
Pickadate.js
A mobile-friendly, responsive, and lightweight jQuery dateinput picker
metro-bootstrap
Simple bootstrap from Twitter with Microsoft’s Metro style.
Making an accessible dialog box
Making an accessible dialog box
The main elements required to make an in-page dialog more accessible, including a neat tabindex trick.
WordPress Post Editor for Balsamiq
WordPress Post Editor for Balsamiq
Template for working on WordPress the post editor UI in Balsamiq Mockups.
WordPress Post Formats Admin UI
WordPress Post Formats Admin UI
Nice plugin from Alex King that adds tabs to the WP admin UI so that you can post nicely-formatted posts using customized UI for each format.
mockupress
“Keynote template for quickly creating awesome WordPress admin interface mockups”
Select2 2.0
Beautiful replacement for simple SELECT box. Supports searching, remote datasets etc.
Uniform
“Sexy forms with jQuery”