Here’s what I posted in a similar thread long ago. Only Exapno is still active, apparently.
My faves were Eats Crayons and Runs with Scissors
I believe they were related. 
I love the name Fluffy Sniffle Picker.
Or is that Pickle Sniffer.
Doesn’t matter, I like the name.
Exapno Mapcase
I have no idea what it means, or why I like it, but it’s number one in my book.
mmm
Harpo Marx, as it seems to read in Cyrillic.
I just recalled Susie Derkins. Any Calvin & Hobbes reference is good. There’s also CalvinHobbes which isn’t IMO nearly as good. I’m surprised to see there’s no Calvinball. If I was forced to change names that would be one of my first picks.
Some names are kinda mysterious. e.g. Francis Vaughan. According to wiki, he was a minor Roman Catholic official in England about a hundred years ago. So either there’s a literary reference I’m clueless about, or there’s an interesting backstory we’re not getting.
I also like Stranger On A Train. Both for the fine Hitchcock reference, and because in many ways the name matches the persona; we know his area of expertise very well, and virtually nothing of the rest of his world. Despite 14,000 posts, he’s still a mysterious shadowy figure; that guy you see on the 8:54 most weekdays but have never shared a word with.
:smack: my head said that but my finger didn’t listen.
While seconding kambuckta’s and stui magpie’s nominations**, I’ll also add carnivorousplant, *Mean Mr. Mustard and Amateur Barbarian.
*[SIZE=“1”]And that’s not just because you’re there, floating above me like some floatygimpy novelty bobble either, Mean Mr. Mustard. I buggered off for a minute, came back, and there you were.[/SIZE]
and let’s not forget Enola Straight .
.
…
…
…
…
…
Because it took me a whole minute to figure it out.
When I saw the name, I first thought "gee, what’s that taken from?–maybe “Enola Crooked, or something?”…
(Yes, when the light bulb finally lit up, I felt kinda , well,… dumb.)
I like the name **Mangetout, **though apparently a few people think it means “man get out.”
ah yes…I impressed myself by not even realising it was a word until that Doper name later helped me work out a crossword clue. Mangetout ignorantly fighting ignorance…!
It feels rude to be here and not mention *those I’ve not mentioned…umm…oh I know! Reality Chuck, Stink Fish Pot and Scumpup. Mucusy and adorable.
*I fear this could go on a long time…
I’m another who finds ‘It’s Not Rocket Surgery’ awesome.
But when the light hit you it was really REALLY BRIGHT, wasn’t it? 
I’ve always found This Just In . . . to be clever - every post sounds like breaking news.
I like the name Ellis Dee.
One of my own favorite names (and favorites Dopers) is Shirley Ujest who has been a while posting.
I used her name in a search for other threads where User Names were the main topic and came up with these that you might want to examine for other names not yet mentioned here:
Whose Username do you wish you had thought of first?
06-17-2014, 08:08 AM – 06-24-2014, 11:53 AM
"Aha! THAT’S what that Dopername means!
08-09-2010, 08:45 PM – 08-14-2010, 06:15 PM
Doper User Name Ultimate Cage Match!
02-14-2009, 08:59 AM – 02-22-2009, 05:43 AM
Oh! I finally got it! I always mentally read it as “Wookie in a Pub”. :smack:
+1
I like having **Cal Meacham **around. One day he may teach me how to build an interocitor.
Is Tequila Mockingbird still around?
Thudlow Boink.
Mentioned before but worth repeating: Freudian Slit.
I’m not sure they still post but my favorite was Baby Fish Mouth because it’s one of my favorite Movie lines that no one remembers.
The most awesomely classic movie *Dr. Strangelove *is well-represented.
We have **Merkin Muffley **& Merkwurdigliebe (although misspelled), Dr. Strangelove, Dr. Strangelunch, and Dr. Strangemind. We don’t have General Buck Turgidson, but we do have his aide, Stainz (although misspelled and probably unrelated). So the War Room is well-represented.
Out at Burpleson Air Force Base we have General Ripper. Although his aide, RAF Group Captain Lionel Mandrake is sadly MIA. As is US Army Col. Bat Guano.
Aboard the B-52 we have Major Kong. The rest of the crew is also absent. Perhaps I should say instead that they’re all still aboard the B-52 while **Major Kong **has abandoned ship for the SDMB. 