I spend lots of my time at a whiteboard diagramming current or proposed systems. The whiteboard experience is less than ideal: my handwriting isn't great, folks on the other side of a VC can't see, etc. Most diagramming software is designed for careful human placement to get precise results. I built Architype to let me take notes and play with system designs in real time during a conversation, in a way that can be easily projected. It's designed to be entirely client-side and fast, but still powerful enough to produce useful diagrams for most purposes.