You know what makes a math nerd suddenly cool? Making $15 million a year and driving a Maserati to the grocery store. Sure, you're a douchebag, but you're a douchebag with money. Who's getting a wedgie after calculus class now, jocks?
There's a pretty huge difference between being able to dunk and knowing all of Xavier McDaniel's home game stats for the 1994 season. The former is called an athlete, the latter is called a statistics nerd. But since they nerd out about sports, it's totally socially acceptable and almost expected in certain circles. I mean, when there are bars based around a fetish like this, you know you won't get beat up for being into it.
Being a car geek, like being a sports geek, is all about an obsession with numbers. But because those numbers are relating to things like torque and ratios and horsepower that come together to deliver the pleasure of going real fast in a hot car, this is seen as a pretty macho hobby. Of course, if the obsession is more with the vroom vroom noises than the mechanics of the engine, you lose out on the major upside of being a geek: brains.
There are really two types of music geeks: serious music appreciators, and musicians. Sadly, making music is less cool than really liking to listen to music if you don't play in a rock band. Those band camp jokes don't come from nowhere! So sorry, flautists! You will never be seen as cool. And there are a lot more flautists out there than there are Sammy Hagars.
Being super into movies is pretty socially acceptable, although there are definitely subgenres here. Being super into art house films? Very cool. Being super into horror movies? Less cool. Repeatedly having your heart broken by George Lucas but continuing to obsess about everything he does? Completely unacceptable.
Liking to eat is one thing, but becoming really familiar with the exact time and water temperature to cook the perfect soft-boiled egg? Knowing the names of every hot chef and where they cook? Tracking exactly how far the basic ingredients in your meal travelled to get to you? This elevates hunger to a seriously geeky level, one that often makes people insufferable pricks to eat around. "Oh god, McDonald's? I haven't eaten there in years!"
As kids who grew up with Atari grow up into adults purchasing Xboxes and PlayStations, video games are looking less like toys and more like a huge entertainment genre. Hell, it's tough to find a male in his 20's who isn't a gamer these days, and the video game population is only getting larger and larger. But still, if you try talking about your favorite elemental sniper rifle from Borderlands or your best killstreak in Modern Warfare 2 while at the country club, you are going to be looked at like a child.
Here's one that we're pretty familiar with around these parts. While the popularity of gadgets such as the iPhone and Xbox 360 have made fetishizing shiny plastic objects much more acceptable and mainstream, being a zealous fanboy or a senseless early adopter will still get you funny looks by more casual gadget users and appreciators. Because really, if you get a hard-on for firmware updates, no girls will want to talk to you unless you build said girls yourself.
Everyone loves their huge selection of iPhone Apps and the amazing software that allows them to do so many different things on their computers, but the folks who actually make this stuff are still seen as shut-in geeks. That's slowly becoming less and less true, as programmers such as the Google guys and Mark Zuckerberg turn code monkeying into billions of dollars, which certainly helps reduce the stigma. But still, Zuckerberg seems like a huge douche, so it may be a wash.
DIY Computer Geeks
Building your own computer is becoming more and more of a niche activity, with laptops becoming the computer of choice for most people and video games moving to the console space. But there's still a seriously active group of people who love the satisfaction that building your own rig brings, and the air of superiority it makes them feel for being able to navigate the nearly impenetrable world of PC components. And man, don't tell them you "custom ordered" your Dell unless you want to be faced with a halitosis-tainted laugh aimed right at you.
You see cosplayers most often at conventions, such as ComicCon. Basically, they dress up like their favorite video game or movie characters, often with a stunning amount of detail. But really, no matter how much effort you put into your costume, if you're dressed up as Cloud from Final Fantasy VII, there's a limit as to how cool you're going to look.
These folks are totally obsessed with Japan and its anime culture, collecting all sorts of figurines of either huge-breasted fantasy girls or shy-looking schoolgirls and having bookshelves full of manga books and anime DVDs. They replace normal social interactions with hours spent fantasizing about a world that doesn't actually exist. Sad would be the word for it.
Dungeons and Dragons is pretty geeky, but it's a board game, so it's done in the privacy of one's home. Not LARPing. LARPing is like taking D&D into the real world by dressing up like orcs and knights and such and having a big, fake, embarrassing battle in a public park. There are no winners in these battles, only losers.
There's nothing below Furries at the bottom of the geek barrel. These folks dress up like human/animal hybrids, often for sexual-fantasy reasons. As much as I want to say "go for it!" to anyone with an oft-mocked hobby, well, this proves that even open-mindedness has its limits.