ImageOptim - Faster web pages and apps.
WinDirStat - WinDirStat is a disk usage statistics viewer and cleanup tool, inspired by KDirStat.
Node.js - Node.js is a platform built on Chrome's JavaScript runtime for easily building fast, scalable network applications
WizTree - WizTree quickly finds the files and folders using the most space on your hard drive. It scans the MFT (Master File Table) instead of crawling the entire disk which makes it very fast.
Ruby on Rails - Ruby on Rails is an open source full-stack web application framework for the Ruby programming...
TreeSize - TreeSize tells you where precious disk space has gone to.