KSpread
KSpread is a free spreadsheet application that is part of KOffice, an integrated office suite for KDE desktop. Among KSpread features are multiple sheets per document, assorted formatting possibilities, support for more than 100 built-in functions, templates, chart, spell-check, hyperlinks, and data sorting.
KSpread native format is XML, compressed with zip. However, KSpread has the ability to import in several spreadsheet formats, including Microsoft Excel, Applix Spreadsheet, Quattro Pro, CSV and OpenOffice.org Calc.
