Building Eric's and other answers here, but answering as an only-ever-so-far-interviewee, what I would like in an interview is a kind of pair-programming 'test', where you sit down together facing the screen, and talk through a real-world problem.
I think there would be many advantages:
- For the interviewee, being in front of a screen instead of facing the interviewer makes it easier to think about the problem rather than the interview.
- For the interviewer, being with the interviewee while they look through the code and ask questions about the problem space would give a much greater insight into how the interviewee thinks, how they approach problems, and how they communicate and interact with others.
I would expect that it's more important and interesting to see a candidate thinking round the edges of your real-world problem, even if they don't completely solve it, than to have them get 10 out of 10 on come algorithmic test.