PDF Tools and Resources
Command line tools and other libraries for use with PDF files.
flpsed is a WYSIWYG pseudo PostScript editor
Multivalent is a set of command line java based tools for manipulating PDF files, such a merging, and page rotation.
PDf City is an on-line PDF flight checker and imposer. Free with a reasonable size limit.
Appligent offers a command line tool for stripping attached files from PDF files. Virus/Worm writers have attemped to use this method for delivery in the past.
An excellent collection of PDF tools, as well as a portal about PDF editing, conversion and other tricks.