I've heard from a salesperson or two over the years that there is truly no "last" thing that happens to a Prospect or Customer. For those of you who have been thinking about instituting a Follow Up policy can do so relatively easily in GoldMine.
You must first enable automatic followups by going to Tools | Options | Schedule.
Select the checkbox labeled "Prompt to schedule a followup activity when completing...".
Ok your way out.
Now, when you go to (for example) to Complete | Unscheduled Call | Incoming Call, you'll notice that the "Schedule a Followup..." checkbox on the lower left is automatically enabled. What this does is open up a Schedule Dialog immediately after the user clicks "Ok" to finish the Completion.
Certainly at that point the new Scheduled activity can be scheduled into the future as is appropriate.