Just a thought folks :

I needed to set the color of a listbox item that depends on a value of
another item that is not visible. In practice I was listing hyperlink
names, but not showing the actual hyperlinks themselves (a non visible
field from the database).
Setting up a single row subform I can then use conditional formatting
on the field that is visible and use the
Expression is .... [OtherField] > " "  (or whatever)
and can set the text to underscore blue indicating a hyperlink.
I'm sure that using 'Expression is' will help a lot of folks who want
colors depending on other control values on the form.
The hyperlink is not relevant to this thread but for those that are
interested:
Application.Followhyperlink (myhyperlinkfield)

Mine is a simple example but could be extended to have multiple colors
depending on different control values for different rows in the
subform(what now looks like a listbox!)

Cheers