The GNOME Structured File Library is a utility library for reading and writing structured file formats. Support for MS OLE2 streams is complete, as is zip import. There is also support for document metadata and some initial work on decompressing VBA streams in OLE files for future conversion to other languages. This library replaces libole2 and is used in gnumeric, mrproject, abiword, libwv2, koffice. It is also part of the AAF format.
PHP Spreadsheet_WriteExcel is a collection of classes for generating Excel files with PHP (without using COM), based on John McNamara's Spreadsheet::WriteExcel from CPAN. It supports all the basic values for cells (strings, numbers), and formulas, images (BMP), and URLs. It is also included in PEAR.
phpWebSheet is a Web-based spreadsheet application that stores data in a CSV file. It features a one step undo function, support for cell functions like =A1+A2 or =sum(E1:E8), Wiki-like text-styles (headings, bold, italics), cell borders, clipboard integration, insertion, deletion, and shifting of cells.
Calligra is an integrated suite of applications that cover office, creative, and management needs. It offers applications on both desktop computers and mobile platforms like tablets and smartphones. OpenDocument Format (ODF) is used, making it compatible with OpenOffice.org, LibreOffice, and Microsoft Office. Calligra Suite contains the following applications: Calligra Words (word processor), Sheets (spreadsheets), Stage (presentations), Flow (diagrams and flowcharts), Kexi (visual database creator), Braindump (note taking), Plan (project management), Krita (drawing), and Karbon (vector graphics).