highlight.js - Highlight.js is a syntax highlighter written in JavaScript. It works in the browser as well as on the server.

EssentialPIM - EssentialPIM is a free Personal Information Manager that keeps up with the times and lets you manage appointments, tasks, notes, contacts, password entries and email messages across multiple devices and cloud applications.

code-prettify - Code Prettify is an embeddable script that makes source-code snippets in HTML prettier.

Todo.txt - Track your tasks and projects in a plain text file, todo.txt. A todo.

Apache Tika - Apache Tika toolkit detects and extracts metadata and text from different file types.

Task Coach - Task Coach is a simple open source todo manager to keep track of personal tasks and todo lists.