I've seen a lot of companies have a jobs section on their websites that talk about what great places they are to work, and the kinds of skills they are looking for along with an email address for people submit resumes.
But I myself wouldn't submit anything to a company this way unless someone at the company suggested it.
And I suspect that people who send their resumes this way are either junior developers looking for job, or developers who are desperate for a new job. So I'm not sure how many diamonds you might get.