I'm trying to create a basic testing application, and I'm hoping to find an open source solution that will allow me to input questions and multiple choice answers (similar to the SAT). I'd like to be able to tag the questions and answers with metadata (topic, subject, correct, incorrect etc), and be able to generate results and metrics based on these tags. Ideally, this database will be scalable - so that I can continue to add questions to it on an ongoing basis. I'd also like to have other authorized users add questions as well. My goal is to produce a simple web application/widget that will deliver questions and answers to users, and give them some feedback and metrics once they have finished a test. Does such a thing exist?