We are constructing a lightweight, viral interface consisting of a button and screen strategically positioned around public spaces to foster social interactions. Users will be able to upload messages for display on the screen when the button is pushed. The idea is to explore if a simple, one-dimensional input device and a small output device can be powerful enough to encourage people to share information about their shared space and spur joint social activities. The work includes building an application environment and collecting and analyzing data on the emergent social activities. Later work may involve tying identity to button-pushers and providing more context-aware messages to the users.