“Seven Fathoms and still dropping sir. Should we be concerned?” 
Thanks to all who replied with an honest, direct answer. I’ll check out a few of the sites mentioned. xkcd does look interesting - I think I saw that 'toon long ago, but forgot about it. It’s pretty funny, IMO.
Regarding my post upthread, I just wasn’t in the mood for snark right out of the gate - been in a bit of a pissy frame of mind lately due to some things out of my realm of control, know how it is sometimes?
Thanks again for the suggestions so far.
Curiously (or perhaps understandably) my next posts have been accepted without moderator input. I suspect they are guarding against bots. They required a double captcha validation, which is the first time I have ever seen that. So, I suppose they have been attacked before. It isn’t as if xkcd is not well-known. Especially to computer geeks.
I recommend looking for a forum for whatever model of vehicle you might own. Even if you’re not into DIY stuff, it’s a good idea to check once in a while for stuff like:
recall notices
technical service bulletins
tire recommendations
chat about ways to fix common issues/annoyances with your vehicle
aftermarket parts/accessories
a heads up on mechanical issues other owners are having so you know how to spot them
what current owners paid if you’re thinking about buying
service, maintenance, and owners manuals
I lurk at www.customerssuck.com. There a few people who can’t write, but there are also a lot of people who are really really funny. And it seems like everyone there is really nice.
For technical questions, try [noparse][H][/noparse]ardforum. For audio-visual kit, try AV Forums.
I lurk occasionally on Pprune (aircraft) and Arrse (British military).
The Archie Comics Fan Forum is specialized, but friendly.
Oh, and also try Fathom.
I am convinced that almost all of the posts are by a handful of people under different names. It’s a site for retail cashiers / workers, of which I am one, and I find the grammar and storytelling to be impeccable. This is frankly unbelievable. Even brand-new members there write like intelligent people. Again, unbelievable.
Joe
Giraffe boards were set up with looser rules than the SDMB. The elder Unaboard took the opposite tack: the goal was to have a somewhat higher level of civility. It’s a nice place to hang out, especially for science fans. I confess to some amusement that apparently there is much less demand for a polite board than for a more raucous one. So far today there were 23 posts at the Unaboard, 79 at Giraffe and 407 at the SDMB. http://unaboard.coalgoddess.net/
Participation is by invitation only. Kidding. I just wanted to type that.
Far more technical than SDMB, but good info is available at eng-tip forums.
I only quoted raindog because he might find the HVAC/R forum there interesting.
I like the forums at the James Randi Educational Foundation.
Gallifrey Base is the best Doctor Who forum. Mods are easy going. Its a fun board.
Some of the tv show boards at TWOP are good. Mods there are very, very tough. Read the rules ten or more times before posting. Better yet, read the rules 25 times.
We mostly manage here. And there are a number of people there I can’t read because they don’t capitalize, or break things into paragraphs, or the incidents are presented in such a boring way I can’t be bothered. Most of the interesting people there are so different from each other that I can’t believe they’re all socks. Perhaps I just have more faith in people (except the stupid 
)
For a couple of specialty topics:
For responsible gun ownership, The High Road has been useful.
For Prius information, Prius Chat is good.
J.
I like Snopes.
The one forum I enjoy the most is LUVTruck.com • View active topics Everybody there seems to be needing help, wanting to help, or just share what with each other.
The nice thing about the internet is no matter how crazy you are, it will unite you with the handfull of similar people.
Most of the dog forums are awful, full of show breeders, dog food reps, snobs. old wives’ tales, knownothings, trolls, and worse.
I think the forums at City-Data.com Forum: Relocation, Moving, General and Local City Discussions are interesting. There are general discussion forums as well as forums for each state/large metro area.
A lot to be said for JREF, though you’ll know fewer people there.
Funny. Several billion people on this rock, but knowing somebody else is still a nice thing.
I like the Ars Technica forums, mostly it’s an educated technophile crowd.
http://arstechnica.com/civis/index.php
Plus, there are some damn funny and clever people there.
Plus, if you want to kill a whole day or two, the funny image thread is a classic…
If you’re into crafting http://www.craftster.org/forum/index.php is the best messageboard for it.