   Abacus is a small, light and easy to use spreadsheet being developed
as graduation project under the tutorship of Prof. Arlindo Oliveira,
and the spreadsheet is being developed using the Tcl/Tk toolkit, as
well as plain old C/C++ for all the "number-crunching" tasks.
The following functionalities are available in the latest version:
   Multiple spreadsheets, limited by the amount of memory you have
available. Small set of built-in functions that include statistical,
financial, and the usual math and trig functions, including a slick
menu-like interface to make it easy to paste formulas. Cell editing
with all the usual Cut/Copy/Paste/Delete functions implemented. Cell
formating with a load of different formats, plus fonts, italics, bold
font size and borders. Column and Row insertion, deletion, resizing.
Sorting using all sorts of weird sort methods, so many we find it
confusing ourselves and we made it! Autosum - you select and press the
button and it sums the data up the way (we hope!) you want. Graphs you
can delete, move around and resize. Printing via Postscript.
Imports/Exports CSV,Tab separated, Wk1 and TinySheet (for the popular
PalmPilot organizer) formats.

WWW: http://www-cad.eecs.berkeley.edu/HomePages/aml/abacus/abacus.html
