Excel is certainly packed with features, but I use a few free add-ins that make Excel even better.
[Update] I’ve created a list of all the free Excel add-ins that were suggested in the comments. Thanks for sharing your favourites!
Name Manager
by Jan Karel Pieterse of JKP Application Development Services
If you use names in Excel, you need this tool. You can quickly find names with errors and delete them, or track names that link to another workbook.
There are many more features, so download Name Manager, and see what it can help you with.

Excel Utilities
by Rob Bovey of AppsPro
Rob’s add-in has handy tools for working with named ranges, worksheets and selections.
You can quickly protect and unprotect all the sheets in a workbook, remove unused styles, and my favourite – centre across a selection, without merging cells.
There are many more features, and you can read the full description on Rob’s page for Excel Utilities.

Pivot Power
Since I work with pivot tables so often, I created my own pivot table add-in, that you can download.
The commands that I use most often are Clear Old Data, and Sum All Data.

Your Favourite Free Excel Add-Ins
What are your favourite free add-ins for Excel? Any of the ones that I’ve listed? Have you created some of your own?
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Hi Ross,
Yeah, I guess they are worth something. Neither is a polished product yet, they are good enough for me, but not for the market.
I’ve written a few:
http://www.codeforexcelandoutlook.com/blog/add-ins/
The most popular one seems to be Random Data Generator.
Debra – Re “and my favourite – centre across a selection, without merging cells” – Were you aware that you can do that using regular Excel? On Home tab in Alignment group, click drop down arrow on lower right. In the drop down box under the word Horizontal, select “Center across Selection”.
I’ve written about my favorite Indispensable Excel Utilities, but here’s a recap of my list.
My favorites for Excel:
Jan Karel Pieterse’s Name Manager and AutoSafe
Rob Bovey’s Chart Labeler
Ken Puls’ XLG Favourites
My favorites for VBA:
Carlos Quintero’s MZ Tools
Rob Bovey’s Code Cleaner
Stephen Bullen’s Smart Indenter and VBE Tools
Free add-ins I’ve written myself and posted:
Change Series Formula
Label Last Point for Excel 2007
LOESS Utility for Excel
I want to echo Bob’s comparison of JKP’s Name Manager vs. Excel 2007’s lame version, which improved a lot on the classic dialog, but fell far short.
JP, your random data generator is great. I have used it a bit, currently updating for 2007 which I will send you.
Jon, I am impressed. You spelt favourites correctly