There are plenty of ways to skin a dead cat.
You could also use a custom numerical format.
FormatCells > Number > Custom
then feed in the string
#,##0;-#,##0;
where the final semi-colon is important and the minus sign can be even more important.[ ] (This assumes that you are restricting yourself to integer numbers.[ ] If not, minor changes are required.)
I often use a variant of this, where I like a small marker instead of the zero.[ ] I use the "·" character (ANSII code = 0183), and so the custom string becomes
#,##0;-#,##0;"·"
The use of the · character serves two purposes.[ ] It confirms for me that the cell is not empty, while not being as visually obtrusive as the 0 character.[ ] In a tabular layout the presence of the marker rather than blank space helps to emphasise the tabular presentation and to guide the eye in following the rows and columns if the table is heavily populated with zeroes.