There is nothing that beats seeing someone's actual code, or having them do a live coding exercise. Even if it's pseudo-code.

Playing the quiz game is unrealistic, and you'll only end up with developers who are good at taking quizzes. I haven't really seen this be a good indicator of the developer's actual skill.

Now, if you're just looking for replaceable cogs, then I guess any quiz would work. Personally, I prefer that I work with developers who have good critical thinking skills and are able to elucidate their intentions when it comes to writing software.

"There is nothing that beats seeing someone's actual code", completely agreed. A good way to see this is to let some problems to be solved and sent with the curriculum, like those acm-icpc problems.

You need to decide how important this is to you. When you mention the words "cheaply" and "quickly" as part of your hiring process - you shouldn't be surprised to what kinds of results you get - especially if you get poor results. If you rely or use some sort of certification test especially if you rely on somebody else to do it, you will most likely miss out on the aspects of the interview and the person that tells you how they handle stress, pressure, challenges and time compression. Sometimes, the best interviews are when you can observe "first hand" how someone deals with a problem and solves it - do they struggle with it but work their way through it and shine, OR do they hit a brick wall and break down putting blame all over the place. If you feel you don't have the expertise to hire someone based on skills required, then bring along a team or other individuals to hit those areas. But then again, that kind of hiring process would drive your costs up but you still need to consider your long term costs of hiring the wrong people.

Try to find out how passionate the developer is about his work.