The game concept I like the most is the Special Events system, which allows multiple tactical options that are almost equal in strength. In general I think the Youth Academy is the best feature in the game as it creates a close connection to your own players.
Some of my Hattrick friends I've known for more than a decade now, which is longer than quite a few of my real-world friendships. You build up trusting relationships with them, and meet people you'd normally never meet. That's also what I really enjoy about the federations in Hattrick - some are really places where you can share your personal stories. A federation in Hattrick was one of the first places where I disclosed I was going to become a father!
What I like about the Hattrick community is that there are real people and you don't just compete against the computers. You play against each other, but you can also help each other in the forum and talk about everything.
I ended up playing Hattrick because I used to play some MMORPG in the past (like Dark Age of Camelot or Ultima Online) but they were totally absorbing and some of my friends described Hattrick as "easy and casual", and I believed it (lol). I couldn’t really guess, at that time, how much time and passion I would end up putting into this game.
What I like about the Hattrick community? Everything. I like all the help you can get in the forums about the game, but also for everything else it gives you in everyday life. Hattrick is my favorite social network.
In HT, my biggest achievement is to be the assistant manager of the U20 national team of Suriname. And of course also, when my dream came true and I reached the third division with my own team!