enthusiastic amateur cook
compressed gases and chemicals
military history, especially tactics and military technology
fiber optics and broadband connectivity & construction
amateur parent
I am quite an expert on (1) trade show exhibits and displays; (2) safety standards for chain saws, leaf blowers, and string trimmers; and (3) public library operations. I’m just waiting for someone to post the question “I’m planning to set up an exhibit about chain saws at my local library. How should I go about this?”
There are also a number of pop culture items (Terry Pratchett novels, Newsradio, Buckaroo Banzai) that I have spent an unhealthy amout of time studying.
I did a bit of research using neural-networks and neuro-physics. Know a thing or two about martial arts (especially Bujinkan Budo Taijutsu). Was a helper in a traditional English taylors shop. Worked in a very high security UK government agency. Have spent the last few years admonishing databases (mostly Oracle). Know what it is like to be long term depressed (and study the medical litterature on anti-depressants). Know how to cook well in several cuisines.
This reminds me of the line from somewhere or other.
A woman said she fell in love with her husband instantly, when he said that he had two undergraduate degrees - one in civil engineering, and the other in invertebrate biology. Thus the only thing he was qualified to do was build zoos for insects.
Don’t know if I am an expert in anything. I have experience in:
[ul][li]Mainframe programming[/li][li]Christianity[/li][li]Western literature[/li][li]Martial arts, especially judo and jujutsu[/li][li]General trivia, although nowhere near the level of some Dopers, who are scary[/li][/ul]Nothing useful.
Regards,
Shodan
My degree is in Environmental Science. And Music (voice). So I’m qualified to sing about the joy of mud. 
or maybe “It’s not easy being green…”
And 15 years of working for a state environmental agency. I used to write regulations, now I answer questions from the public and industry. All kinds of idiot questions. sigh.
Wrote and published a cookbook. MMMMMMmmmm recipes.
Married 10 years. Still not an expert in that.
I’ve had Chronic ideopathic hives for 5 years now. Ask me about antihistamines!
I’m an insurance broker by trade, so I usually try to chime in on any of the “I just had an accident-Help!” threads, provided GingeroftheNorth hasn’t beat me to it.
I was a waiter/bartender for 10 years, so I can usually answer any questions about that. Doesn’t come up too often, and many Dopers have worked in the industry as well.
I also have a far better than average knowledge of movie trivia and 80’s pop culture.
I’m also one of those people that no one wants to play against in Trivial Pursuit.
I wonder what a Doper Trivial Pursuit tournament would look like…
Really Not All That Bright asked a question very much like this not long ago; my answer then:
I neglected to mention quality control and quality auditing in this list – another thing I’m not expert in, but I have professional knowledge that most lack.
Another insurance broker checking in - they are not so common out here - but specialising in energy sector. Previously risk manager with one of the oil majors, petroleum geologist and way back a mining geologist. Reckon on a certain level of expertise still on all that stuff.
Interested, but no expert, in history, especially military history, tramping, rock climbing and mountaineering, cooking, MG cars, rowing racing fours and eights, board games and cooking (italian). Trivia buff from varied reading list.
Always willing to opine, but finding I fight more of my ignorance here than I might dispell… I guess thats a plus. 
Whoah!
I’d forgotten about that one.
I fixed cars/trucks for 15 years, so that’s about the only questions you’ll ever see me answering over in GQ. Automotive-type (received an AS in Automotive Mechanics and had state and ASE licenses).
Other than that, I may answer questions about:
The Who
Star Wars (the original trilogy–haven’t followed the latest)
Japanese History/Culture (got a BA in that but it wasn’t my career, so have promptly forgot a lot of stuff. I MAY remember some things 
)
Kid-stuff (I have a 3 year old and a 2-month old–I suppose that doesn’t make me an expert but we’re all here to help each other out. Right? Right!!!)
Mostly I’m here to read and learn. I try not to answer stuff I don’t know for fear of looking like an ass, but I don’t always succeed.
By trade, I’m a trainer for a computer corporation, so I know a bit about teaching and adult-learning theory, as well as some stuff about computers.
I’m also a former DJ, so I end up throwing in my $0.02 on that industry as well.
My stock in trade these days seems to be as a pop-culture expert. I think I could easily challenge just about anyone here on Survivor trivia, and I’m pretty darned decent at general movie and TV trivia as well.
I have been around the block a few times, and to strain the metaphor I’ve made a lot of turns into blind alleys. I think I’m back on track now, but my list of jobs shows the various experience I can share:
[ul]
[li]Newspaper delivery[/li][li]US Army, Infantry squad leader (TOW anti-tank weapon)[/li][li]User assistant in a college computer lab[/li][li]College cafeteria worker[/li][li]TV rental service guy in a hospital[/li][li]Telemarketer (4 different places)[/li][li]Direct sales (latex exam gloves)[/li][li]Door to door steak salesman[/li][li]Seller of personal security devices[/li][li]Office manager for small company[/li][li]Ice cream truck driver[/li][li]Telephone survey interviewer[/li][li]Telephone survey quality control monitor[/li][li]Network hardware repairman[/li][li]Owner of a consignment shop, used sales[/li][li]Publisher of a small advertising circular[/li][li]Dish network salesman[/li][li]Dish satellite internet installer[/li][/ul]
Around all this, I have been DM for D&D and similar games for 24 years. Right now I am studying for my A+ certification exam for computer repair, following up on my college education in computer programming. (I didn’t get a degree; but I finished 3 years of college (in 5 years.))
Oh, and the Stillers. I study the NFL closely.
…and of course I forgot to mention that I’m a TV fiend and can talk trivia with the best… especially things Trek.
Steelerphan reminded me that I know lots and lots about Buccaneers football (although not a great deal about the pre-pewter days), and NFL rushing statistics.
I’ve got an undergraduate degree in math, so I’m no expert, but I’m pretty far ahead of the average person. I’m also one of about three or four people on the boards with an interest in computation theory, although I’m not an expert there either. I know a thing or two (or more) about heavy metal, and I’m a beginning powerlifter, which seems to be a rare specialty here.
I’m a bridge engineer so I can answer questions about bridges and a little bit about roadway design. And the occasional building structural question if I happen to know it. (although my math skills are obviously deficient, I totally humiliated myself trying to answer a math question one Saturday night after few beers. I’m never doing that again. Remember kids, don’t drink and post!)
I also row and coach rowing (there haven’t been any rowing questions 
) and have lifted weights for years. Plus I do a lot of fitness reading so I can answer most questions on fitness and nutrition.
I’m a former record store manager and book store employee so I know a lot about how those industries work.
And I’m a redhead and can field all those numerous redhead related questions. 
Id like to think that Im the resident Electrician here, but I think there are a few of us, - like Casdave for one. I may be the only Union Journeyman Electrician on the boards.
So, what year did Paddington Bear play for the Atlanta Braves? I’ve been wondering.
For myself:
I work in the semiconductor industry, and could answer a lot about how microchips get made, but that’s not a very common topic.
I also read a lot of SF – as do a lot of people here, it’s not exactly a rare commodity.
And I’m interested in Math, but ultrafilter is invariably fast to answer any math questions, so what can I really add?
Does anyone know lots about fluid mechanics? Specifically, can you tell me what the hell they are?
['lil hijack] Most of us who* did experience * The Dead can’t tell you either <sic>