ExcelToDBF is an open source Add-in for Excel 2007 written in VB.NET.
Add old Excel 2003 menus to Excel 2007. Excel 2007 or higher required.
Converts VBA source to the Microsoft Excel Workbook and Excel add-ins.
Add-in for Excel that allows you to query using SQL within the Excel application.
Spinnaker Software Solutions
Spinnaker Dbase Tools is a compilation of various add-ins designed for Excel.
It is the most useful collection of add-ins for people who use Excel.
Lyquidity Solutions Limited
It's an Excel 2007 add-in which allows a user to find the combination of values.
ChartQuick is an Add-in for Windows Microsoft Excel 2007 .
QuerySmith is an add-in for Microsoft® Excel® 2007 and 2010.
Xls to Xlsx Batch Converter convert Excel 2003 to/from Excel 2007.