From 0 to MongoDB in 30 seconds...

example.sh

# Run the following steps in your terminal...

# make sure you have node and mongo installed
npm install strong-cli

# create a loopback project
slc lb project mongo-example
cd mongo-example

# create a loopback model
slc lb model todo

# tell loopback you want to use mongodb
# add the following to datasources.json
...
  "db": {
    "connector": "mongodb",
    "url": "mongodb://localhost:27015"
  }
...

# hit mongodb from node
# add this to app.js
var Todo = app.models.todo;
Todo.create({
  title: 'install loopback and connect to mongodb',
  done: true
});

# start the app in the background
node app &

# hit mongodb over REST
curl localhost:3000/api/todos
[{"id": 1, "title": "install loopback and connect to mongodb", "done": true}]

# learn more here
open http://loopback.io