People training to kill other people; there is almost nothing else more exciting and impressive to witness. The human body can be pushed in unfathomable ways, and the mind, doubly so.
I have a fascination with the Nazi's as if anyone can't tell by this point, mainly due to their use of symbolism and an empirical mentality, but also because of their bureaucratic efficiency in weeding out "enemies of the state". This is before even getting down to their brilliant military tactics and their ability to pump out such loyal soldiers. But another group I've been digging recently is Spetsnaz GRU.
Spetsnaz GRU are the result of throwing pipe-hittin' Russians into one of the most rigorous training programs ever known.
The Russian military is full of badass motherfuckers. From the sacrifical tactics utilized on World War II (Minefield "tramplers" come to mind) to just about any current and former special force, all classified as Spetsnaz, there is a reason Russia is one of the most feared and impenetrable countries, and a reason why you'd never want to be on the wrong end of a Spetsnaz hatchet throwing. These guys are fucking hardcore.
There isn't enough time in the world to learn everything I want to know about everything, but next time I take a trip to the bookstore, I know the topic of interest I'll be searching for.