JExcelApi is a java library which provides the ability to read, write, and modify Microsoft Excel spreadsheets. This project mirrors the files on http://www.jexcelapi.org, which has been known to go down on occasion.
A C#/.Net library for creating powerful reports in Excel from an Excel template. The template can modified by the costumer (just basic Excel skills are needed) so each costumer can influence the design of his reports (e.g. bills).