There are times in life when we learn things that are going to be of little use to us as we make our way in the world. Since leaving school I have had little cause to unearth from the depths of my memory such facts as the battle of Agincourt being fought in 1415 or that Fray Bentos is a town in Uruguay. Nor will I ever, unless perhaps one day I am sitting in a chair facing Chris Tarrant.

As far as I know schoolchildren still chant those mantras that begin "one nine is nine, two nines are eighteen," or whatever, as the times tables are laboriously etched into their minds. Of course learning these tables is a very good numerical foundation on which to build, although calculators are so prevalent today, being found on PCs, mobile phones and even watches, that mental tables need rarely be referred to.

Similarly, the Highway Code still includes sections on hand signals and heaven help the driving pupil who has not studied them when he or she comes to take the theory test. Yet, in all my years as a driver I have never once seen a fellow motorist use a hand signal (well, I have, but you would not find these particular ones in the Highway Code as they are generally not performed to warn other motorists, but rather they involve the use of an extended middle finger). But you never know when you may be asked to mark the board for a game of darts, and you may notice that your indicator bulb has popped when you have to drive home at a busy time of day, so learning is never time wasted.

After that introduction, it will come as no surprise to learn that Excel also has some tricks up its sleeve that there is apparently little need for, but that are there anyway. For example, dates in Excel are, by default, separated by strokes, as in 25/10/1415 (the date of Agincourt). This is all well and good and everyone is at home with it. But if you wanted to be a bit of a rebel and print that date using hyphens instead (25-10-1415), then Excel can do this.

Simply select the cells you want to format and right click. From the Context menu that appears, select Format Cells. Select the Number tab and choose Custom from the category list. Enter the date display separated by hyphens into the Type box as d-m-yy, and click OK. Back on your worksheet, type a date into the selected area as usual, using strokes to separate the figures, and when you hit Enter it will automatically convert to hyphen separation. You can also use other punctuation marks as separators, such as full stops and commas.

In an Excel workbook the cells are separated by light grey gridlines by default. These lines are only there as a guide and they do not appear on printed sheets. However, there is nothing to say that you should settle for dull old grey gridlines, even if they are for on-screen viewing only, and switching to a snazzier colour is a simple task.

For pre 2007 versions of Excel, go to Tools and choose Options. Select the View tab and check the Gridlines box. Click the Gridline Colour drop-down list and select your colour. Click OK.

For Excel 2007 you should click the Office button, then Excel Options. Click Advanced and scroll until you come to Display options for this Worksheet. Check the Show Gridlines box and select your colour from the drop down box as before. Click OK.

So there you have a pair of tricks from Excel's 'Rarely Used' file. You never know, you may have cause to use one of them one day, but even if you don't, learning how to perform even these tasks will increase your knowledge of Excel and how it works. Enrolling on a training course would allow you to explore in far more detail the wide world of this fantastically versatile application.