Microsoft Excel is such a powerful and pervasive software that is used by so many people in so many places for so many uses. However, despite its importance in many people's works, many do stick with the limited set of techniques they know, and has no initiative to learn new ones which may potentially save him/her a lot of time and effort everyday.
Fortunately, with the help of a search engine, it's easy to find solutions to many problems, and techniques to save time and effort. Besides that, I would like to recommend a free ebook - Learn Excel 97-2007 from MrExcel. Which I found to be a valuable resource.
There are 377 "mysteries" in the book and so, you can go through it in about one year for one "mystery" per day.
If you have time, it maybe a good idea to go through it page by page. You may find out something that is so useful to your everyday work that you never knew before. And you don't have to study and memorize each technique in details. One of the good things about the ebook version is that, you can search inside it. So as long as you know there's a certain technique, which you only use once in a long while, you can find it out using some keywords when you actually need to use it.
Now, when people ask me about Excel, I often send this ebook (or an excerpt of it, or the link to download it, because the "low-res" version takes about 12MB compressed) to them and tell them in which page to find the solution. In hoping so they not only find the solution, but also know that such a resource is available and ready for them to use and to learn.
This book covers which in my opinions, basic (sometimes even trivial, but may not be obvious to many) to advanced Excel techniques - Pivot table anyone...?) It does not cover much, if any, VBA stuff. For that the author has some other resources, but VBA maybe an overkill for most of us.
The free downloadable version has a cavaet - The graphics are "low-res" and the author claims it's not suitable for printing. Although I have tried once and think the quality is acceptable, but you may have another opinion. There's a "high-res" version available, suitable for printing as claimed, which costs USD9.95 as of writing.
A print version (i.e. book) can also be bought, if you prefer something to hold onto or put on the shelves, for USD39.95 listed, and it includes instructions to download the "high-res" ebook for free (and by the way, you can probably find it at cheaper prices elsewhere).
