Here is a plot - assuming you have the time and interest. Take a friends phone, change your name [or the name of another person in on the plan] in his address book to one of those numbers given e.g. change njung'e to one of those numbers. Obviously you should do this discretely - maybe as you are having a summit. The person who's name was changed then calls the person and [obviously] instead of the name appearing it's the number that appears. Come back and report the reaction

I saw this trick played on a guy those days when Safcom used to call guys telling them they've won a milli. The name was changed to 0729333333 [The number Safcom were using to call guys (was very publicized)]. All I can say is, the reaction and what followed [the joke was taken a bit too far] was just hilarious!!!