Oh, so many things. Astronomy, biochemistry, science fiction, politics, music, etc. It's hard to pin down any one thing that I can say fascinates me more than anything else.

Probably a lot like /u/spaceghoti 'damned near everything'. Top three that come to mind at the moment...

- Quantum Mechanics - when you have molecules rolling up inclined surfaces and light waves acting different depending on if someone is looking or not, then you know shit's just got weird.

- Bayes' theorem - if your spam filter works, then you can thank this reverend from 1812 for writing down the probablity algorithm to make it work. I've played with it in Python some and it's amazing.

- Game Theory - I just scratch the surface of this. The concepts are pretty far-reaching.

I'm fascinated by strangers and, by extension, people! I love speculating why they're acting the way they are acting, guessing who they are, what they do. I love to hear them talk of their histories, their ideas and dreams! I'm also silently judging them too, which I can't seem to help.

If I had an hour to spend as I please, where I please everyday, I'd go people watching in the busiest places in the world.

Strangely, I'm an introvert.

There are two things that I've always been fascinated with.

The first is artificial intelligence, or more-so, deconstructing intelligence/behavior down to actual programmable contents. The brain is just a very powerful supercomputer, and a lot of what humans/animals do is simple if/then scenarios. If anything, I'm fascinated by human nature and I want to understand it in a way that makes sense to me.

The second is "theoretical" science. I really love "what if" situations or "this event happens, how does the planet as it is respond to it?" I also really like geological theory especially (such as making a world scientifically accurate where it's moons properly affect the planet, and the land masses are scientifically accurate although fictional), as it takes a key part in worldbuilding.

Our/my place in the universe. Its so incomprehensibly large its baffling.

I was driving down the road the other day and just thinking about what we know about the romans, and what people 1600 years from now will think about our cultures. Then it hit me how random it is that my "consciousness" is set in this day and age and not one hundreds/thousands of years ago, despite every molecule in my body being made from a star. Its really incomprehensible to me, but still fascinates me nonetheless.

MAGISTERLUDI

I'm fascinated by nanotechnology - how we're able to create things so small that the laws of physics change. In not even a hundred years, we went from gears and steam engines to transistors so small that they are on the edge of quantum physics.

The stars.

I'm in to 'old' computer stuff... MUDs, old programming languages, text-based interfaces.

Much like /u/spaceghoti, /u/gnomeshell & /u/papervoid I am fascinated with all things to with space. I might not understand a lot of the complex things although I love reading about stuff and trying to puzzle together some of the theories involved, but damn I love it all.

It fascinates me that some people believe that life only exists on earth and how some people can kill in the name of a being which they have no real proof exists

Like /u/Fuyu and /u/newuser, how the human mind works is incredibly fascinating to me. In particular, despite having looked into and practiced hypnosis for about two years now, there's still so much to find and new information to discover on the subject. It's fascinating to me both for how many different ways it can be done, and how it ties into how the human mind functions. (For instance, Transderivational searches are key to some means of inducing a trance state.)

I think one big thing wouod be the human psychie (not sure if thats how it's spelt.)

So for example, I have recently been taking on a bunch of new hobbies and am just loving learning new things. This includes having taken on learning python. I spent the other day doing essentially what I would imagine could easily be considered tutorials for a starter course on python. As a student at varsity, I always had this feeling of disdain for work I "HAD" to do, and so I would drag me feet and do the bare minimum. Now that I don't need to do it, I'm spending hours doing just that and loving it. Where was the joy in the work at varsity. Why is it that because I needed to do it, did hate it so much? I would have done so much better had I been this excited about my work at varsity.

It's also not that I was doing the wrong work because I have had a similar reaction to work in the field I studied. Also I found my friends all had a similar reaction to tutorials and homework. We are strange beings.

That's just an example I have looked at how our mind works and gone, that is just so bazaar and illogical.

Languages, quantum physics, politics, economics, and Fallout New Vegas.

People, I love meeting people of all types. Sooo many varieties out there!

That fact that there's no such thing as up or down in space. Measurements of orientation are totally arbitrary while you're floating around in the dark simultaneously towards and away from infinity.

I absolutely love watching traffic on a busy road, if I had the chance and the time, I would watch for hours on end.

Genealogy is my thing. I could sit forever and trace back the to the roots of myself or other people, its too damn interesting.