Excel

Addix
Suppliers of financial, mathematical and statistical function libraries and tools for use in Excel, VB and VBA
http://www.addix.com/

Alan's Excel Page
Alan Barasch's guide to Microsoft Excel. A collection of macros, formulas, and links.
http://xl.barasch.com/

Anthony's VBA Page
Mathematical example programs for Excel. Anthony Sun.
http://www.geocities.com/WallStreet/9245/

Archives of Excel-G
A mailing list where the general or casual user can get help. Free registration required.
http://peach.ease.lsoft.com/archives/excel-g.html

Archives of Excel-L
Developers mailing list. Presents messages from 1994. Free registration required.
http://peach.ease.lsoft.com/archives/excel-l.html

David McRitchie's -- My Excel Macros
Excel macros and usage notes to help beginners and fairly advanced users.
http://www.mvps.org/dmcritchie/excel/excel.htm

Excel Basics
Beginner's tutorial topics include how to type in data, change column widths, add formating, adding formulas, insert charts, and sort selected cells. Features snapshot examples.
http://www.quasar.ualberta.ca/edpy202/tutorial/spreadsheet/ExcelBasics/ExcelBasics.htm

The Excel Logic Page
Provides free downloadable files built using advanced techniques. Presentation of the author and contact information.
http://www.xl-logic.com/

Excel Tips
Offers tips, tutorials and help for spreadsheet design and VBA macro programming.
http://www.exceltip.com

The Excellent Files
Provides files for download and tips. In the Netherlands.
http://www.rosenkrantz.nl

Fred Cumming's Excel Page
Excel 5 workbooks compressed with pkzip and saved as self-extracting archives. User forms, macros, and utilities.
http://www.netspace.net.au/~fcfhsp/xlhome.htm

Macro-Investment Analysis in Excel
Using named ranges and matrix operations. William Sharpe, Stanford.
http://www.stanford.edu/~wfsharpe/mia/mat/mia_mat4.htm

Microsoft Excel Development
How to develop spreadsheets using VBA, includes demonstration macros, sample program/code, and information on FOCARB: a program that re-balances investment portfolio book values.
http://members.allstream.net/~johnjaz/excel.htm

OzGrid Business Applications
Excel add-ins, templates, and training.
http://www.ozgrid.com

Peltier Technical Services, Inc.
Information and tutorials about Excel charting and other tips and tricks.
http://peltiertech.com/

Worksheet Server
Web server allowing the deployment of spreadsheets as a true PHP-based multi-user application.
http://www.jedox.com