Opensort is general purpose sorting software that aims to be a fast and easy solution for the sorting of large or small data-sets and data manipulation in general. It is still in the early stages of development and lacks many of the advanced features its commercial counterparts have. For the moment, it only provides a simple command line interface and a C library other programs can use to cover some basic needs for data sorting.
Proview is a PDF editor that allows you to merge and split files; rotate, flip, and scale individual pages or all pages; crop pages; and modify the document information. It can edit encrypted files, and can decrypt and encrypt PDF documents. You can also manage PDF bookmarks, add or remove PDF attachments, and add text and dates to one or more pages. Proview has a simple, clean interface with all functions easily accessible, and it comes with full interactive help.