NBT.js 
by Sijmen Mulder.
NBT.js is a JavaScript parser NBT archives, for use with Node.js.
Usage
After var nbt = require('nbt'), you can use nbt.parse(data, callback) to convert NBT data into a regular JavaScript object.
var fs = require('fs'),
nbt = require('nbt');
fs.readFile('bigtest.nbt', function(error, data) {
if (error) throw error;
nbt.parse(data, function(error, result) {
console.log(result.Level.stringTest);
console.log(result.Level['nested compound test']);
});
});
If the data is gzipped, it is automatically decompressed first.
Tag names are copied verbatim, and as some names are not valid JavaScript names, use of the indexer may be required – such as with the nested compound test in the example above.
Development and testing
Grunt is used as a task runner:
grunt jshint # Check code quality
grunt test # Run tests
grunt watch # Do the above two on every file change
Known issues
Copyright
I, the copyright holder of this work, hereby release it into the public domain. This applies worldwide.
In case this is not legally possible: I grant anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law.