Let's see...
-I collect zombie movies. I've seen most of them over 100 times each, I never get enough of it.
-I'm a gun nut/gun lover/walking firearm encyclopedia in a country where owning a large picture of a gun could raise a few eyebrows from the local authorities. -> thus I play airsoft furiously as my only available substitute.
-I'm a tinkerer. I take things apart, try to learn their inner workings and in 99.9% of the cases I put them back together the right way. And amazingly, they still work. The 0.1% that fail, tend to do so in quite a spectacular way. I've also "saved the day" multiple times by fixing (read: patching) things in the middle of nowhere, with zip-ties, duct tape and spit. I never part with my EDC Kit which is filled with a load of "day-saving" crap.
-I'm also awesome with a sewing machine, a chainsaw, an angle grinder, I can use a lathe or a vertical milling machine, operate a bridge-crane or an excavator, pick simple locks, and all of this thanks to my Superhero Grandpa who insisted I should learn these things.
-I'm into geocaching, hiking, traveling, sight-seeing, as long as I do it on foot. I'm addicted to walking.
-I'm a gamer, and I've been playing computer games since 1985. Mostly I just waste my time in some open-ended sandbox game that people have stopped playing 10 years ago.
What kind of nerd does that make me?