I always have enjoyed data visualization and simulations. From my days as a teen when attaching oscilloscopes to analog sources such as the music stereo receiver and “watching” the music, to my days as a computer science student visualizing data structures and logic flow (and simulating the immediate (heat) effects of nuclear explosions). A picture (or animation) is worth a thousand (and thousands of) words.
While I haven't coded information visualization in a long time, it is cool to see visualization software such as Digg Labs' Swarm and Stack which shows in real-time Digg's current activity and relationships between entries and users.
When designing your software piece keep "information visualization" in mind as part of your overall information architecture strategy, and design into your software the “hooks” and data models that will allow you to code data and activity visualization later on.
ceo