Drunken parrot UI kit
Here’s a beautiful, flat style UI kit, called the “Drunken Parrot”. This version is free, and it comes with both HTML (based on Twitter Bootstrap 3) and PSD files.
All of the elements included are part of Twitter Bootstrap 3, there are a few custom elements for fun. A 980px grid was used to ensure optimal flexibility for the majority of people, and free fonts and icons were used for this free version.