Gaydar

According to the BBC, a study by the Philadelphia's Monell Chemical Senses Center, published in the Journal of Psychological Science found that "gay men were found to be particularly good at detecting the scent of other gay men". If this proves true, it could provide the beginnings of some level of credibility for the concept of "gaydar".

Moreover, William Lee Adams, an undergraduate at Harvard College, recently conducted a study on gaydar for his senior thesis. The process included showing neck-up pictures and videos, without any jewelry or makeup, to homosexual men and women and heterosexuals. It was a single-blind study, inasmuch as the volunteers did not know the purpose of the study until after the process had been taken place. The results portrayed gay men and gay women as having a higher tendency than straight people to correctly identify homosexuals (they also were able to identify sexuality quicker in an average time of two seconds). However, gay men were more easily recognizable than gay women. It was hypothesised that this was because of their more visible niche in the media.
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This is what I got My Gaydar must of been off tonight
You personally got 12 of the 20 people correct and were better at recognizing guys than girls. Overall, you guessed better than 29% of all test takers.