What do you think about posting job vacancies and then notify people through their emails?
If you were to receive the email would you read it or delete it?
What are the chances of it being a business to generate a substantial income?
Lastly, if you were the one sending the email how would you title it?

Thanks.

Jacaranda, my view is that this will largely depend on the reputation of your service. I changed jobs some time in the past through a posting made to my E-mail address from www.jobserve.com.

Unlike Kadonye's case, I am subscribed to that site. Job sites are common place in the developed world. I am not sure whether that is the case in Kenya.