saved from a previous post:
There's nothing that can be done just by clicking.
You could do it based on a doubleclick or rightclick -- but maybe this
alternative will work.
Select your range that should have this behavior (I'm gonna use column A).
Format|Cells|number tab|custom category
In the Type box, put this:
X;X;X;X
Now, anything you type in will look like an X (spacebar, x, Lee, anything!)
And if you want to find out if a cell is an X, you'll have to use something
like:
=if(a1="","nope","Yep")
(hitting the delete key on the keyboard will clear the cell)
Another alternative--if you want something that looks like a checkmark:
Format|Cells|number tab|custom category
In the "type:" box, put this:
alt-0252;alt-0252;alt-0252;alt-0252
But hit and hold the alt key while you're typing the 0252 from the numeric
keypad.
It should look something like this when you're done.
ü;ü;ü;ü
(umlaut over the lower case u separated by semicolons)
And format that range of cells as Wingdings.
All that other stuff still applies.