Football Scores is a demo application for node.js and MongoDB. The back end is a express 4 rest service while the front end is a simple jQuery & HTML5 Web App. The application is in Spanish. The rest api is hosted in the OpenShift cloud. GitHub.
Project Euler is a set of mathematical problems to solve, you can start by brute forcing solutions but after the first few questions one needs to figure out how to solve them mathematically in order for your program to finish in a reasonable amount of time. GitHub