The goal of Rx is to coordinate and orchestrate event-based and asynchronous computations such as low-latency sensor streams, Twitter and social media status updates, SMS messages, GPS coordinates, mouse moves and other UI events, Web sockets, and high-latency calls to Web services using standard object-oriented programming languages such as Java, C#, or Visual Basic.
via: Erik Meijer (2012): "Your Mouse is a Database", http://queue.acm.org/detail.cfm?id=2169076