I was tempted to join some of the others in making a goofy response, but nah, I'll be serious. For the sake of context, I am a heterosexual male.
Stockings and thigh highs and knee high socks. Just all sorts of long leg wear like that does it for me. Bonus points if it's paired with a skirt (there's a
Japanese term for that combo as well, which makes internet searches a breeze). I'm not just talking about seeing women wear such things around normally (though I do enjoy that as well), I'm talking about wearing this stuff in bed. However, sort of counter to most people who are into this apparel kink, I'm not really into the Catholic schoolgirl look.
I like dom/sub play as well. I'm cool with both sides of it, but I generally prefer dominant women. Fun fact: I realized that this preference was not the norm when I was talking to some 6th grade friends about celebrities we thought were hot and they gave names like Britney Spears and Jennifer Love Hewitt, and then I said Lucy Lawless (dat Xena, mmm) and got a lot of weird looks. Good times.
Light bondage is real neat too. A little bit of rope to secure the hands, or maybe some cuffs instead? I'm down. Full body leather suits and crazy extreme rope setups that make it so the person can barely move? Nah, I'll pass.
That's all I can think of for the moment. Nothing super exciting, but there it is.
EDIT: Diana makes a good point. The above is just things that excite me in real life contexts. I have a wide array of other weird shit that I like to see in fictional areas, but I feel like this isn't the thread for that stuff, so I'll leave my post as is. 8D