I have a few,
Flying: I absolutely love flying, its what I want to do for my career in the military. I have 50 hours of flight time in Cessnas and even that gave me the feeling of freedom that I really love. Its also full of danger at times, and its absolutely intoxicating. My instructors would chastise me for it, but the idea of being out there over God knows where with just your plane and your skill: amazing.
Firearms: I don't mean just shooting on this one. Of course thats the best part, as its really a test of your skill and proficiency in a practical skill. It also has a real zen aspect to it. Its just you, your weapon, and the target. When I am on a roll(which thankfully to my practice is becoming more frequent every time) its just great for my entire psych. I feel clean and calm afterwards and can think better and faster then before I was shooting. In addition to this though, I love the firearms themselves. The mechanics of the weapons fascinates me to no end, sometimes to relax at home I disassemble and reassemble my AK and Glock a few times, sometimes doing it blindfolded, sometimes going for speed, ect. I also love the history of weapons and their usage and development over time.
Hiking/Outdoors: Hiking for me has the capability of bringing all of my loved elements of life together. Exploration, reliance on yourself, a sense of self drive to go further and faster, but also I think it brings me closer to nature and God. Theres also those moments of accomplishment, I mean, if you've ever reached a mountain peak and just stood there and looked out over the landscape you know what I mean. Also, its zen for me. Its peaceful, even when the going is tough. Gives me time to think, or the luxury of not thinking at all, just enjoying what I see.
Armed Exhibition Drill: For those who don't know what this is check here [http://www.youtube.com/watch?v=1FGnYy4jxfA]. I got into this after I got into AFJROTC my freshman year of highschool. I think that it has above all the others has directly contributed the most to allowing me to mature and grow as a person. I was on our Drill Team for four years, I chose my successor as Team Commander only a few weeks ago. It helped me gain discipline, strength(literal and figurative), and without it I wouldn't have been able to build the most important friendships in my life right now. Like everything else here, theres a certain Zen to it, yet a certain danger as well. I have hurt myself more then once, and have risked serious injury countless times on some of our more interesting maneuvers. I would do it all over again. Thankfully there is a great team at the college I am attending, so hopefully lighting can strike twice.
History: When it comes to academic passions, history is definitely paramount. I love examining details of battles, studying cultures, and trying to see myself in every situation. The questions of who, what, when, where, and how are always presents in events. You have to look beyond the cover, to see the real root of issues. It gives insight into our world today, and offers wisdom you can find no where else.
Interestingly enough I would not consider video games a passion of mine. A couple of years ago I would have said it was without a second wasted, but now? Not so much. I still love them, but its a hobby now, not a passion. Thats a good thing too, I will probably be doing very little gaming over the next few years(yay military college!). All of my passions involve a few basic things: skill, zen, and danger. If these things come together I'm all over it.