I think in every profession there is always a certain tool which is so important that the professional would have one very personal to his heart. He loves using it and would not think of using any other. For the chef would be his knife, for the samurai his katana, for the gamer his perfectly aligned customized and calibrated mouse (who on earth in his right mind would buy a 500 ringgit mouse???). But I consider myself a programmer and the tool close to my heart as a programmer is my editor. Oh how I love my editor, namely vim (please don't flame me, I like emacs too but don't use it anymore).
So while I was just idly surfing around looking for inspirations I bumped into this page entitled "Bill Joy's greatest gift to man" and it gives an interesting view on the origin of vi (vim's much revered parent). In the article in mentions "So the editor was optimized so that you could edit and feel productive when it was painting slower than you could think". We don't live in that kind of world now. Our computers could probably render 3d worlds faster than we can imagine them now, but still the feel productive part is essential. How productive? Look at Why, oh WHY, do those #?@! nutheads use vi? to understand. :D