As an undergraduate, I wrote a textbook for Real/Modern Analysis to complement my studying of the subject. My goal with the text was to present the subject more intuitively and more visually than is usually embraced by the formal texts.
The format of the book is modeled after Edward Tufte's designs for his books, particularly Beautiful Evidence. It was created using the Tufte LaTeX document class which can be downloaded here.
The hallmarks of the Tufte's books include wide margins and extensive formatting for figures and tables which, in addition to being aesthetically beautiful, are also well-suited to the study of Analysis with ample room for side notes and small figures.
To complement the material, the text is filled with number line and geometric diagrams which attempt to elucidate concepts. I have found that the study of Analysis is extremely visual and that concrete examples make the theorems much easier to understand and internalize.
Many thanks to my professors and classmates at Columbia for introducing me to the subject of mathematical analysis. Of course, my notes are not a faithful representation of my courses; in particular, any errors are entirely my own. Similarly, any virtues are attributed to my lecturers and peers.