Most methods in GTD are logically quite obvious, but I'm unsure of the solution to this one.

Suppose you have an item you want to give to a friend in person (i.e., it can't be posted).

You're not sure when you're going to next be seeing this friend, so it can't be put in your calendar.

It's not good to put it in an action list, @Friend for example, as when you check this list (when you're with them), you won't have thought about the item to give them.

My only conclusion is to get into the habit of checking the action list of somewhere I'm about to go, before I go there. But this won't work all the time.

Anyone got a better solution?