It's not a "hidden talent" per se, not like I can bend my big toe in the opposite angle, lol, but I am a really, really good theater actress.
I was awarded tons of awards in high school, from local, state, and national associations. I was in school plays, local plays, and touring off-Broadway plays. I was even offered full-ride scholarships to several different universities.
Of course, I shot myself in the foot when I got pregnant and married at 19, but I'm thinking about trying to get back into it.