I found this article while adding some equipment to LensTag (a theft recovery site for photographers www.lenstag.com) about the use of prime lenses and the advantages over the popular zooms. I do my best work when I am using primes and it the article seems to echo my own thoughts, however in a way which is going to be easier to understand them my babbling. I completely agree that a fixed focal length forces the photographer to think, move, and think some more. Pictured below is one of my favorite and oldest lenses still in use, a Nikkor 50mm f/1.4 prime. This was my primary lens for many years when I was working with 35mm film and it resides on my D800 a majority of the time as it lacks the gadgetry and associated weight which is found on modern lenses.
Without further delay, the link: