To be more specific, I have this field sitting next to the portal. The idea is to have it display data from the record in the active portal row without going to that record (GTRR) Seems like a simple thing, but is it possible?
Have another relationship from the table of that layout. Create a global field gRecordID (or some meaningful name) and relate it to the portal's table occurance, by gRecordID = the unique RecordID in that table.
Attach a script to the portal row that sets that gRecordID by picking up the RecordID of the portal row clicked on.
Set the fields from the portal row's record that you want to see, on the layout, using that new relationship.