QuarkXPress 10 has the new functionality to show the missing font in your document. The Highlight Missing Fonts feature makes it easy to find text that uses a missing font in a layout. For example, you have a document, in which the fonts have been used, which are not installed on your machine. When you open the document on your machine, this feature marks the missing fonts in the specific color, which has been chosen in Highlight Missing Fonts function. You can even change the highlight color in the preferences.
For more information please find the link below:
http://www.quark.com/Products/QuarkXPress/Features/Precision_Typography.aspx#14