[ul]
[li]reading[/li][li]gardening[/li][li]poker[/li][li]astronomy[/li][li]bicycling/motorcycling[/li][li]canoeing[/li][li]backpacking/camping[/li][li]hunting/fishing[/li][li]skiing (xc & downhill)[/li][/ul]
I write novels (mostly in my own original series, though I used to write fanfic novels in the game universe I freelance in, and just completed a real to-be-published one in the same universe)
I freelance for a game company (writing fluff bits for sourcebooks–see above, but short pieces)
I play tabletop RPGs (Shadowrun, Savage Worlds, and we’re starting a FATE campaign next month–I’ve played many others since college)
I play MMORPGs (though intermittently these days–I used to be quite addicted, but that’s over now. World of Warcraft, Star Wars: The Old Republic, and The Secret World)
I’ve become quite the Whovian over the last couple of years.
I play with my cats.
I don’t know how to quote just your last two paragraphs but I think you just described a golfer.
I write. I read. I crochet. I research prehistory, Medieval times and the Gilded Age. I salvage castoff things and make something else out of them. I paint. I used to sing (still try.) Since I can’t sew but love textiles, I’m into creating fabric pictures (kind of like a collage.) I refinish furniture. I make lots and lots of lists.
I also dance at the drop of a hat.
Not necessarily. I make a sugar wine that when clarified and concentrated through fractional freezing is for all intents and purposes a very vodka like substance. In fact if I gave you a shot and asked you what it was you’d most certainly say vodka. No distillation required.
Me, my hobby is collection hobbies.
I get interested in something, research it, buy the paraphernalia, work at it for 6 months or so and get distracted by something else - wash, rinse, repeat.
I wonder if that is the difference - i.e., getting back to msmith’s point about devoting geek time to an interest.
I love to cook, write, study art and philosophy, do yoga and many other things. But I wouldn’t say I am a cook or writer in the same way I feel very comfortable saying “I am a guitarist.”
I would consider them all to be interests/hobbies of mine, but appreciate the question of degree.
Shooter or shootist?
Shootist sounds cooler.
I basically have every stereotypical “nerd hobby” other than ham radio and model trains.
Magic : The Gathering; Warhammer 40K, Dungeons and Dragons (and other RPGs), Comic Books; Anime; Movies, TV, and Reading; I’ve collected action figures in the past but the lines I was interested in are basically over with. I do board games, when I can. I paint miniature figures (for use with D&D and Warhammer).
I do some programming, but mostly professionally, these days. Also, Video games are currently taking up a lot of my free time.
I enjoy non-sport sports like Air Hockey, Mini Golf, and Bowling, but rarely get to indulge. I do exercise regularly, though I don’t know if that’s a hobby or not.
Occasionally I’ll take a stab at learning to draw, but I hardly have the time to learn to do it properly - just look at how much else I have to do!
Motorcycling when the weather is warm and dry enough to suit me. I’m planning on getting a larger touring motorcycle in the spring and taking longer trips.
I practice catch and release knife collecting. That is, I buy them and put them in my collection for a while and then give them away as gifts. I recently acquired Camillus Cyber which will be going to my nephew as a Xmas gift.
Shooting, both firearms and crossbows, is another favorite activity. I hunt, too. No joy so far this year, but winter archery season is coming up.
In terms of stuff I do on a close to daily basis, I guess cooking and videogaming should be listed here.
Not sure if you’re into Reddit; but there’s a subreddit sub for that.
http://www.reddit.com/r/PenmanshipPorn/
http://www.reddit.com/r/Handwriting/
http://www.reddit.com/r/penmanship/
Computer games
Computers
Hiking
Biking
Chickens
Canoeing
Planning for world domination (slow start)
I feel like studying the nature of the hobbyist has taken on a hobby status with me. It is a facinating study on its own.
Winemaking. Grow my own grapes and make my own wine. I’ve always used my own grapes but will branch out this year into getting some different fruit for blends, maybe mead also, I’m getting bored with the same ho-hum batch every year.
Guitar playing. I have a small collection and like learning and playing at home for myself. I’m trying to find the time to learn some recording/mixing to preserve some of the cool stuff I’ve occasionally come up with. Never performed in public though.
Martial arts. Been dormant for a few years, but still study it and practice every now and then.
Well, now that I think about it, I do have a beard, flew in a helicopter 20-100 ft off the ground to get to work yesterday, and do indeed prefer Dos Equis when I drink Mexican beer…
I suppose “boating” could be a hobby. Or it’s just “boating”.
Playing sports aren’t hobbies. They are “playing sports”. Collecting sports memorabilia or joining a fantasy football league is a hobby though.
Yeah…I think brewing beer qualifies as a hobby at 1 gallon.
You don’t have to be obsessive about it. But IMHO it’s the sort of thing that requires you to actively learn how to participate in an activity that is fundamentally pointless for anything but your own enjoyment. As soon as you start repeating the activity and trying to do it better, then it has effectively become a hobby.
I think that hobbies usually have some elements that set them apart. Creativity or problem solving is very often a key element. At some level the hope of discovering new frontiers or uncharted territory is another. Whether it is fishing, or bonsai, or bow making, dog training, carving etc I am always looking for some little thing that nobody else has discovered yet.
Sewist sounds better than sewer too. 
I sew and knit things. The sewing is mainly tailoring my own clothes or constructing costumes, but the knitting is more meditative, bordering occasionally on compulsive. I tell people that I only knit things that are supposed to come out flat, because I can do that by feel while watching movies. In fact, if any of the other yarn-crafters here have a closet full of useless tiny leftover yarn balls that they are willing to throw into a box and mail to New England, message me and let me know – I ask around for them every winter. Soft wearable yarns get made into rainbow scarves and donated to whoever is having a clothing drive when they’re done. Weird, stiff, or scratchy yarns, especially acrylic, get made into hammocks, pockets, and tunnels for tiny rodenty animals like rats and mice, and forwarded to Mainely Rat Rescue, the regional small caged critter rescue organization.
I also perform, mainly acting and dance. I accidentally found myself a slot as “scream queen” for a local theater group that puts on staged radio dramas, complete with live Foley. Lately I have been hauling large dance hoops (VERY large. I have a 46" hoop I can rest on my shoulder and my heel at the same time) back and forth to rehearsals for a solo number I’ll be performing downtown on New Year’s Eve as part of the city’s First Night celebration. I contend that the fanciest hoop trick I have learned so far is how not to maim the other commuters with them on the train. The second fanciest is how to put the decorative tape on without making a complete dog’s breakfast of it.
I also keep a running blog, although that fails one of Justin’s criteria above. Technically, I am paid for it, as I get $0.30 a month from someone subscribing to it via the Kindle service. 
I collect spores, molds, and fungus…
C’mon, someone had to say it 
Seriously though…
Recreational/sport shooting
Hand loading
Gardening
Raising chickens (free-ranging, pastured birds)
Fishing
Fly-tying
Photography
Knife collecting (Spyderco, Buck, Case, Victorinox, Ka-Bar)
Camping
Nordic and alpine skiing
…of course there is. That should be an adjunct of Rule 34. Rule 34a: If it exists, there’s a subreddit devoted to it. Rule 34a (i): And another devoted to people doing it while naked.
Thank you for the links, though!
I got sucked into this, my girlfriend got sucked into this and niether of us have any idea why???