Here's a good list of available modules https://github.com/joyent/node/wiki/modules. If you get involved in the community you'll quickly discover which ones are widely used in your area of concern. I've played with express http://expressjs.com/ routing and views with the jade https://github.com/visionmedia/jade view engine. I found them quite easy to learn. When I got into node I also got into MongoDB http://www.mongodb.org/ so I haven't played with any ORM tools because there was no mapping of objects to a relation db needed, no mapping at all really since I pretty much keep everything in JSON format from front to back.