Beeping as Metaphor
Throughout Africa, many people will call from one mobile phone to another and deliberately hang up before the call is answered . . . but just long enough to have call missed and a number/name appear. This phenomena is called "beeping" or "flashing".
Beeping itself is free. It usually can be interpreted as a request for the beeped to call the beeper back, thus placing the financial burden of the call on the person beeped (due to most mobiles in Africa being based on prepaid rather than monthly charges). However, beeping can also have more subtle meanings. While seemingly nonspecific, contextually it can send a very specific message such as "I am outside waiting" or "'Thinking of you."
It can be remarkable what is able to be conveyed when you are forced to keep it simple--A ring tone can proxy for freedom of speech, a text message can rally a protest, and a beep can start an affair. It is said that necessity is the mother of invention, but human curiosity and finding new ways to flirt certainly help to move things along. . .

