XESS is a spreadsheet for UNIX, Linux, OpenVMS, and Windows NT which supports user-configurable 3-D workbooks with up to 10 million rows, enhanced display and print formatting, international locales (including multi-byte languages), full Y2K compliance, Web enablement, and a high level of compatibility with the Excel and Lotus spreadsheet products. It includes filters for Excel 97, Excel 2000, and Lotus spreadsheets.
PLOTICUS is a command line utility for creating bar, line, pie, boxplot, scatterplot, sweep, heatmap, vector, timeline, Venn diagrams, and other types of charts and plots. ploticus is good for automated or just-in-time graph generation. It handles date, time, and categorical data nicely, and has some basic statistical capabilities. It can output to GIF, PNG, SVG, SWF, JPEG, PostScript, EPS, and X11. You can use convenient preset options or create complex scripts with rich and detailed color and style operations.
xlHtml converts an Excel spreadsheet file (.xls) into highly-optimized HTML. It includes scripts to allow it to be used as a Netscape or mutt plugin and as a xls handler for Apache. The program currently supports string, blank, boolean, error, integer, floating point, hyperlinks, and formula cells. It can also output in XML, tab delimited, or comma separated values (CSV).
Gnumeric is a powerful and easy to use spreadsheet using GNOME. Its goal is to provide a full featured spreadsheet and a smooth migration path for people and organizations currently using proprietary applications. It provides more sheet functions and greatly improved accuracy when compared to Microsoft's Excel. A plugin system lets you extend Gnumeric, adding functions, I/O formats, and real time data capabilities. The existing Python, Guile, and Perl plugins let you define complex functions. Gnumeric is capable of reading and writing MS Excel (XLS and Office Open XML), and reading Lotus, Applix, Quattro Pro, OpenCalc (ODF), XBase, DIF, SYLK, HTML, Psion, MPS, oleo, sc, misc. text formats, and its native XML. It can also generate Latex, HTML, and others.
Siag Office is a free office package which consists of the spreadsheet Siag, the word processor PW, the animation program Egon, the text editor XedPlus, the file manager Xfiler and the previewer Gvu. Siag is easy to use, yet infinitely flexible through multiple embedded interpreters and a plugin mechanism that allows other programs to run inside the main document. The supported interpreters are SIOD, Guile, Tcl, and Python.