gridfs-rackdav enables you to use GridFS as backend for WebDAV collections with RackDAV application

it said optional

Simple job queue system based on mongodb

Quick and easy mapping with MapPLZ

Lightweight wrapper for MongoDB documents

Simple but powerful tool for managing mongodb databases

ODM for MongoDB

ODM for MongoDB - for Rails 2.3.x

Snapshot your mongodb in the EC2 cloud via XFS Freeze

MongoHydrator takes a document, represented as a Ruby Hash, and efficiently updates it so that embedded references to MongoDB documents are replaced with their corresponding subdocuments.

MongoDB backend implementation for I18n gem.

Simple Mongoid Model to_csv() class method that preserves scopes

Adds Kerberos authentication via libsasl to the MongoDB Ruby Driver on MRI and JRuby

Easy backups for EBS-based MongoDB Databases

Mongomatic is a modular Ruby object mapper for Mongo

MongoDB Pipe powered by PubNub.

A proxy server for MongoDB.

Records time spent in mongo and adds to request logs

Resque is a Redis-backed Ruby library for creating background jobs, placing those jobs on multiple queues, and processing them later. Mongo-Resque is the same thing, but for mongo. It would not exist without the work of defunkt and ctrochalakis on github.

Light-weight sequences for MongoDB, useful for auto-incrementing or counting. Works with any ODM.