Firefox PDF Plugin for Mac OS X

lets you split and join PDF documents as well as insert images and blank pages. You will also be able to easily create PDF documents out of several images.

make nice pdf presentations

combine pdfs

combine multiple pdfs with automator

iPapers is an application that manages many PDF files of articles, whose information can be obtained by PubMed. If you have articles as PDF files whose filenames are PMID.pdf (e.g. 10867176.pdf), you can import the articles into iPapers by drag and drop o

pdf generator

Think of kip as iPhoto for your documents.

command line pdf converter for mac and linux, windows has a gui