You are absolutely right in pointing out Mightyspring. They help especially when you focus on what you want to do. In Jobrupt's case, the focus is on 'with whom you want to work'. It may be your ex-boss or ex-employee, your ex-colleague, your classmate, your competitor, your customer, your service provider etc. Mightyspring definitely deserve their place, Jobrupt is just a different and additional type of job search tool. You don't need to choose one or another, you may use both.