binary_with_request.js

var fs = require('fs')
        , Buffer = require('buffer').Buffer
        , request = require('request');

var outStream = fs.createWriteStream('out.jpg', {encoding:'binary'});
request({'uri': 'http://marcorogers.com/blog/static/content/images/ebook_conversion_success.jpg'
        , 'responseBodyStream': outStream}
, function(err, data, body) {
    console.log('done');
});