Among others, Martini Enfield and **Silenus **know their guns pretty well.
I’ll try to avoid mentioning those already mentioned, but here are some:
Northern Piper - Law. He has an impressive knowledge of various countries’ constitutions as well.
Inigo Montoya - Insurance.
fishbicycle - Rock and pop music.
Sunspace - Environmentally-friendly housing.
RickJay - Baseball.
severus - Quebec politics and separation issues.
Mathochist, Indistinguishable, Jamaika a Jamaikake, ultrafilter, Hari Seldon - mathematics.
Darwin’s Finch - Evolution
Hippie Hollow - Game shows
Anaamika - Indian culture and cooking
Litoris - Cousins with the same name 
fessie - Art
OpalCat - Art
Asimovian - swine and NaCl
Crotalus - snakes
Especially The Beatles. I am a huge Beatles fan, and know far more trivia about the band and their music than anyone else I know, but around here, I don’t even bother trying to answer questions about them because fishbicycle blows me out of the water.
finally the recognition I deserve
Sunspace – solar homes
Cervaise, DevilsKnew, Mangetout – cooking
Mangetout - foraging
ScubaBen – diving
Waverly – cat humor
I think that probably should read “Chowder - Man City”
God, you’re right. He’ll be mad at me for making that mistake – and mad at you for calling him “Chowder.”
Loach - Law enforcement.
God bless you, youngster!
I’m 52…
what kind of puzzles do you do?
Rick - Cars
OneCentStamp - early (1976-1986) punk rock and hardcore punk.
Hey, nobody said it had to be useful.
Thanks, Spoons and Sarahfeena! Hey, I don’t mean to intimidate you with my knowledge about The Beatles! Please come into threads about them and give your observations. It’s nice to talk with people who are knowledgeable.
Everybody has their special thing they’re interested in. Mine was The Beatles, ever since I saw them on Ed Sullivan. So you buy all their records, and take notes on what you have, and what records you’ve seen. Then you find out that there are hundreds of variations on most of the albums, from every country where there was an EMI plant. Then, poking around in record bins at every store you come across, you discover bootlegs. If you want them enough, you will find a way to get them. And I did. It’s been a process of collecting everything I can find and can afford. There is so much stuff! I can’t afford to get into memorabilia, though. Just recordings, photos and books. So start a thread!
I worked at the puzzle factory for many years – all kinds, though my crossword expertise seems to come in the handiest around here.
So…ummm…thanks, grandad? 
Liberal - Everything that can be known
Me - Everything else