HEATKEYS

A-PDF Solution is a PDF software developer who focuses on providing affordable Acrobat PDF tools and customization service for personal and small business.

Sciweavers is a bookmarking network for researchers to share and explore research paper preprints grouped by conference name and year or subject area.

wikiHow is a wiki based collaboration to build the world’s largest, highest quality how to manual. Our multilingual how to manual has free step-by-step instructions on how to do all types of things.

PDF Toolkits for Software Developers

DevProConnections provides comprehensive, independent how-to content on building applications with the Microsoft stack.

Create PDF, encrypt PDF, manipulate PDF or render PDF documents in your applications. Quick PDF Library (formerly iSEDQuickPDF) contains over 500 functions. Royalty free PDF SDK!

Tracker Software Products develops fast, light PDF software for viewing, converting, and editing PDF documents, with unparalleled support and service.

The most comprehensive, popular and independent site focused on Adobe Acrobat/PDF. Sponsored by Nitro PDF, ARTS PDF, PDFlib and more.

Linux blog by Vivek - Includes news, help, tutorials, programming, tips and how-to guides for Linux, UNIX, and BSD.

Bluebeam

PDFMate Free PDF Converter is a 5-in-1 PDF program to easily convert your PDF to editable Text files, common images, EPUB eBooks, HTML files, and even SWF files.