When I embark upon a project, work or fun, I always spend a good deal of time up front just daydreaming about it. Sometimes I do this for months before I get an

When I embark upon a project, work or fun, I always spend a good deal of time up front just daydreaming about it. Sometimes I do this for months before I get anything down on paper. Over the years I have perfected the skill of prototyping in my head - thinking through use cases, what-if scenarios etc. The advantage of this is that it is much faster than anything else - but you have to be able to juggle a lot of stuff in your head at once. The result of this is that I can slowly build a complete mental model of the project in my head so that when I actually start the project I know exactly what I want to make, how I want to make it, what problems I will run into and how to solve them. Work-wise this is sometimes a problem because co-workers seem to think that I often just sit and stare out the window, but when at last I get going they can't believe how fast I get things done.