Pattern Brainstorming

How do patterns emerge?  Mine have come about from a variety of inspirations.  Some patterns come from practical needs.  I needed a new kitchen rug, hence the striped kitchen rug was born.  The perfect dishcloth came about through trial and error as I made dishcloths to fill my needs.  The car and duck washcloths started as baby gifts, and my current lace shawl/table runner (still in production) started with my desire to work on lace and my love of the color yellow for spring.  While working on my current pattern (the yellow lace) I have let my mind wander and the idea of a fleur de lis lace shawl is emerging and a simple lace shawl in a wonderful pink novelty yarn is forming.  My mind and design notebook are full of ideas, and I only hope to have time to get to at least most of my ideas.  Where do find inspiration for your knitting?