As a designer that works primarily with dynamic, and interactive media, I spend a large portion of my day using applications like Adobe After Effects. Actually I spend most of my day bouncing between After Effects, Premier, PhotoShop, Illustrator, and Audition these days. One thing I am always looking for is a way to improve my work, and if possible simplify the process.
Earlier today while looking for a real physics engine for After Effects, I came across Newton. This plugin has been out for a while, and is currently on version 1.2. I however just discovered it, and it looks really promising. Available from Motion Boutique, the plugin features: Gravity, friction, bounce, resistance, elasticity, collision detection, and a time divider for super slow motion.
At around $250.00 depending on the exchange rates its not cheap, but well worth the money if you need an easy to use solution for any of the features mentioned above.