Instructables describes itself as " a web-based documentation platform where passionate people share what they do and how they do it, and learn from and collaborate with others. The seeds of Instructables germinated at the MIT Media Lab as the future founders of Squid Labs built places to share their projects and help others."
It is a great resource for project ideas, ways of using the arduino, problem solving suggestions, design inspiration and how to work with various materials and fabrication techniques.
The resouces of Instructables are best when complemented by your artisitc vision and aesthetic sensibility.
There are a range of searchable categories including: