CodeEval has now introduced 'Sponsored' challenges. Employers can now sponsor a challenge. Something that they would be impressed if any candidate solved. This could be an algorithmic challenge or something from within the employers domain that they encounter everyday.
Once an employer sponsors a challenge, all CodeEval users will see a banner in their dashboard informing them of the challenge and the sponsoring company. They can then proceed to attempt it and if their solution is correct, they have the option of forwarding their profile (which contains their src code) directly to the hiring manager at the company.
Candidates benefit by proving that they are indeed smart and can have their solutions sent directly to the hiring managers. Employers benefit by receiving only motivated candidates who take the time and effort to solve the challenge.
Looks like a win - win :)