Documize - Enterprise-grade wiki and knowledge management platform
Plupload - Multiple file upload utility using Flash, Silverlight, Google Gears, HTML5 or BrowserPlus!
HackMD - Fast and flexible, real-time collaborative markdown, inspired by Hackpad.
Uploadify - Uploadify is a jQuery plugin that allows users to easily add multiple file upload functionality to their website.
ReadTheDocs - Spend your time on writing high quality documentation, not on the tools to make your documentation work.
FancyUpload - digitarald:Harald K - Consultant & Contractor - FancyUpload - Swiff meets Ajax - Swiff meets Ajax for powerful and elegant uploads.