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.
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.
@1 Table Publisher allows you to create, edit, and display Microsoft Excel or Access tables directly via a Web browser. It allows you to create tables from scratch, import MS-Excel/Access tables, or use existing data files on servers. It has support for master login and sub-user login. It also allows two-way import/export to/from MS-Excel/Access data files.
QuantLib is a cross-platform, quantitative finance C++ library for modeling, pricing, trading, and risk management in real-life. It is also wrapped as Python/Ruby/Scheme modules. Extensions for Excel, R, and Mathematica are available. Other such extensions are under consideration. QuantLib offers tools that are useful both for practical implementation and for advanced modeling. It features market conventions, yield curve models, solvers, PDEs, Monte Carlo (low-discrepancy included), exotic options, VAR, and so on.
Spreadsheet::WriteExcel is a Perl module which can be used to create native Excel binary files. Formatted text and numbers can be written to multiple worksheets in a workbook. Formulas and functions are also supported. It is 100% Perl and doesn't require any Windows libraries or a copy of Excel. It will also work on the majority of Unix and Macintosh platforms. Generated files are compatible with Excel 97, 2000, 2002, and 2003, and with OpenOffice and Gnumeric. An older version also supports Excel 5/95.
Sharp Tools is a spreadsheet written in Java. It features full formula support (nested functions, auto-updating, and relative/absolute addressing), a file format compatible with other spreadsheets, printing support, undo/redo, a clipboard, sorting, data exchange with Excel, histogram generation, and a built-in help system.