Perhaps conditional formatting would be a better option <g>

This example assumes you want to conditionally format
an adjacent cell if a certain trigger condition
is activated in another "target" cell

Assume you want to conditionally format B1 to display
the font in red & bolded, if the number in A1 exceeds 10
(A1 will be the "target" cell here)

In B1, you might typed have a text-phrase
relevant to the number in A1, e.g.: "Alert!"

Try this:

Select B1

Click Format > Conditional Formatting

Under Condition 1, make the settings:
Formula Is| =$A$1>10
Click Format button > Font tab > red/bold > OK

Click OK at the main dialog

The text-phrase in B1 will then appear
with font in red & bolded
whenever the trigger condition is activated
i.e. A1 > 10

(Test this out by inputting some numbers in A1)

And for some examples of specifying colour in number formats, see Jon
Peltier's web site:

  http://peltiertech.com/Excel/NumberFormats.html