I still wonder what it would be good for. If I open attachments linked to an order, I already know the order ID, so this wouldn’t give me any information.
If you want to do it anyway, you need decide how you’ll determine which field you’d want to show. I think a good choice would be displaying the AutoIdentification field group. Just don’t forget that it may consists of several fields or something useless to users (e.g. RecId, or InventTransId as on PurchLine).
I think you’d use a data source for Common table and assign the actual table at runtime, which is not completely trivial. Again, I would consider whether the whole thing is worth all the effort.