First, above any other convention that I have went to, DragonCon had some of the best cosplays that I had seen. There were tons of con-goers and it seemed that mostly everyone wore some kind of costume.
Creativity is a virus. It duplicates and grows until it consumes my entire life. I can't speak for every writer, but my insomniatic mind has spun for hours playing out possible scenes for projects that I am working. The heart of creativity lies in creating and to create, most people start with an idea.