Times New Roman by Pedro Javier Arbelaez. This poster in particular is a favorite of mine. I assume this poster goes through the history of Times New Roman. What's great is that Times New Roman is the only typeface used here.
Garamond Type Poster by Melody Shar; The use of few colors creates a simple, clean, and modern look. The "B" acts as a divider between different sections and lets the viewer travel his/her eyes between the sections.