ViewXLS

Features

 * ViewXLS will display some sheet content from Excel files.
 * Export TSV
 * Export CSV
 * Export Drawfile

Limitations

 * Only displays cell content
 * No formulae
 * No objects (ie: graphs)
 * No outlines
 * No macros
 * No pivot-tables

Even taking the above limitations into account, ViewXLS is still very useful as a free Excel Sheet viewer for RISC OS, and as a convertor to universal formats that can be read with e.g. Fireworkz or Schema 2