UI Movement - The best UI design inspiration, daily
UI Recipes - Weekly 15 min lessons on UI design from the hottest apps
UI8 - Carefully crafted UI design assets
UI Garage - Specific mobile and web design patterns for your inspiration
Design Principles - An open source repository of design principles and methods
Theme Forest - The #1 marketplace for premium website templates, including themes for WordPress, Magento, Drupal, Joomla, and more. Create a website, fast.