As part of a project I'm working on, I have a requirement for a NoSQL database. There are numerous offerings out there, of which MongoDB and CouchDB appear to be the most popular. So which system should I choose?
Reactive programming is a paradigm which allows you to better represent a work flow where changes in one part of your data model propagate down to other parts of the model. This blog post demonstrates an example of this, by listening for updates to Wikipedia and reacting accordingly.