I spent the better part of a decade with my head deep in Magic: The Gathering. I spent all my spare money on M:TG cards, I went to tournaments, I crafted decks, and I woke up in the middle of the night with ideas about possible combos.
I never did particularly well. Although I'm a competent player, I was an ordinary deck-builder, and stubborn enough not to net-deck everything. And even though it's been more than ten years since I "retired", there are life lessons Magic: The Gathering has taught me that have nothing to do with gaming and everything to do with living.