I would say that on a formal basis, things like using grids and exploring space both more openly and selectively is something that crossed over between assignments for sure. On a more conceptual note, I've learned the importance of keeping my concept clear and in view at all times during a project. Even if I am happy with my work formally it doesn't really make much difference if it looks good and doesn't say what I want it to. Also being able to let my design be affected more by outside influence and natural objects and occurrences, and integrating those things with my design to broaden my visual style. Last but not least, I have learned to not be afraid of working in analog from time to time (even if working digital is my favorite), and that Flash, while faster, is nowhere near as intuitive as After Effects.
All of these things both formally and conceptually will definitely be useful to me in the future. Now let me just hit "⌘s".