wizdum:
We need to find a way to transfer their calls to another callcentre, so they can just bug each other for eternity.
Hmm, now how would you do that?
Note that they often use a "scheduler" which rings various numbers and only when one answers, does it get connected to a callcentre operator. This is why when you answer the phone, they do not talk immediately - your time is considered of no value but they want to get the most out of their operators (as they demand such high wages). In general, if you pick up the phone and no-one speaks for three seconds or more, you can hang up because it is either a callcentre, kids, or grandma has just had a stroke.
So if you could somehow aggregate a lot of lines, and in particular if you could determine the country or state of origin, you might have a reasonable chance of two such calls being received at once and could connect them.