I've had to interview people for programming jobs before. (Believe it or not. Just goes to show. Those who know do, those who don't, interview. Something like that.) Interviewing people is one of the worst experiences I've ever had. It's impossible to tell how good someone is at anything in a half an hour, unless the skill you're trying to judge is "ability to interview well". So inevitably you start trying to come up with stupid tricks to tease out the details of people's character.
One of my favorite questions was always, "What's your favorite text editor?" You can tell a lot about a person from the answer. It's such a stupid question and it's one that few people would see coming. It can be delivered in a seemingly harmless off-handed way. Only a true geek can see through to the true depth and significance of the question. It's also a question you can't easily fake a good answer to. Here are some possible answers and their implications for hireability.
- "Vim". Insta-hire.
- "Emacs." Close enough. Insta-hire.
- "Textpad." They're probably on the right path, just another sad victim of Windows indoctrination. You may be able to bring them back into the light, given time and careful attention.
- "Eclipse." Sadomasochistic. Proceed with caution.
- "Visual Studio." This person lives in a strange, alien world which I want no part of.
- "EDIT.EXE". Hire this person the next time 1987 rolls around.
- "Notepad." Immediately drop this person to negative hit points. They're not quite dead, but will be dead soon without immediate supernatural recovery.
- "I use whatever." This person wrote three or four programs his entire life, and all of them were homework assignments.
- "MS Word." Avoid direct eye contact and GET OUT OF THE ROOM WHILE YOU HAVE THE CHANCE.
Most of those, I've actually heard. Of course once they answer, you should quiz them a bit further to make sure they aren't making it up. One person I talked to mentioned "vi" but didn't know of the existence of vim, which was kind of suspicious.