Meaningful Transitions is the thesis project of Johannes Tonollo, an interface design student at the FH Potsdam, Germany. Johannes wrote his Thesis on "Transitions in the User Interface," in which he analyzed how motion in the user interface can be a helpful extension to static elements to enhance the user experience.

The collection of transitions is clustered into 6 different categories: Orientation, Spatial Extension, Awaking Controls (Awakening?), Highlight, Feedback, and Feedforward. His description of the effectiveness of each transition forms a pattern-like-library for motion in interface design. Each transition provides a short summary and abstract animation on the category overview. Be sure to click each item to view a detailed view that provides a description of the transition, explanation of when it can be useful, and a description of the benefits for using that transition as a design solution. Several items also provide a real-world example of the solution in use.

Excellent stuff, and impressive execution. Check it out. The thesis is also available in a downloadable PDF in German.

http://www.ui-transitions.com/#home