How can I tell if a gift is from an anonymous donor?

If a Gift is marked anonymous then: User Defined Gift History Export: If exporting the Gift Acknowledgement fields, blank values are exported in place of the Acknowledgment fields.  However, if you are using the Donor Address field, the name will appear.  Be sure to export the Anonymous field from the Gift if you want to see if it is marked Anonymous.

Gift History Export or Gift Acknowledgment Export:

• The Name from the Gift is exported.  (Note: There is a separate column that indicates if a Gift is marked Anonymous or not.) In most Gift reports (not exports) driven from the GiftHistory table (under Gift Reports off the menu), that are at the detail level, Anonymous Donor will show instead of the Annual Report Name.  
• In most Donor reports and exports driven from the Donor table (under Donor Reports off the menu), which are generally summary in nature, the Donor Name will appear (not Anonymous Donor).  This is because most of these reports are summarized and one Gift could be anonymous and another not for any particular donor.  

Pledge Reports:

• Most are summary in nature and will not say Anonymous Donor. 
• However, the Unposted Pledge Listing Report will show Anonymous.  

The Anonymous check box on the Donor record has no effect on Reports and Exports.
Data Grids will not say Anonymous since they are raw report-writers (just like Results).