“Hi Opal” seems to be the standard…
I don’t mind being called Trouble, and some shorten it to TA, both are fine, but don’t allow for vanity searches (though Trouble works better than TA). You’d be amazed how often the word trouble is used in conversation.
js_africanus is formal and acceptable.
js has a nice friendly ring to it, and since I sign many personal notes, letter, and emails as jsh, there is a contingent of people who refer to me as jsh, which sounds pretty close to js thus giving js a nice sound to me.
Alternatively, you can call me x-rated, since my name is mentioned in a Beastie Boys song.
Hmm… I get TheLoadedDog, theloadeddog, The Loaded Dog, the loaded dog, Loaded, loaded, Do, dog, 'Dog, 'dog, Dawg, dawg, 'Dawg, 'dawg, TLD, tld, T L D, t l d, and God knows what all…
Just call me TLD. I’m not fussed on vanity searches, and the three letters is easy. It’s what my friends on here call me.
“theman” isn’t thutch a bad name unleth you thpeak with a listhp!
Dethspicable!
Well, since my SN is an acronym, an abrreviation, and a number all squashed together, I don’t think there’s a good way to shorten it. I’ve been called by all three parts, and it never bothers me.
Mostly I get ‘kam’ (d’uh) but I must admit that I prefer the nom coined by BalmainBoy (who doesn’t seem to hang out much in these parts anymore, unfortunately)…Bucky.
Reminds me of the taunts I got during my school days when I had braces.
LCC
My wife says mine is wayyyy too long…You can call me roland
No worries unsli. 
Or Nott! It seems negative, but I’ve been called Nott since 1965. If you wanna be esoteric, you can call me Sheriff. Just don’t call me the king of refrigerator light bulbs; that would be inaccurate. If you called me Omar, that would be a stretched double-layered gag, and nobody would get it. If you called me Ferrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrnando, I might bow, but only I and a certain Gold-Glover would know why. If you called me a cab, it would mean I’d had too much bourbon.
Yike. I do prattle on, sometimes.
LMAO 
I’d take Racin’. Some folks can call me chikkiboo but racin’s what I shorten it to myself.
And rolandgunslinger, yours HAS to shorten to roland. There’s already a Gunslinger. (I call him Gun. Or “sugarbee,” or “love,” or “you mad sexy beast” or what-have-you. Or, you know, his given name.)
I’m usually pretty pysched when I’m recognized at all. Couldn’t care less whether you call me SFT or Searching or whatever else people tend to use.
There’s a few who still call me JJ. Good times, good times…
How about T-Bone?
None. Pun and punny are also acceptable. However:
'Punha
iamapunha
iamthepunha
iamampunha
ipanema
iampuhna
imapuna
imapunha
The first is just weird, since my name isn’t capitalized (and isn’t meant to be). But the others, as far as I can remember (and there’s one in the pit somewhere that I saw just yesterday), are all invalid spellings I’ve seen at least once. Er, folks, it ain’t that difficult to spell. iam pun ha. Sound it out (though not as it is meant:)) if need be. Not like I’m asking you to spell Mendeleev;)
Ack. Forgot to say that ipanema is a song reference from a Jack Batty post from back in 2000.
I realized today that I have chosen a SN that doesn’t shorten easily; I was thinking 'lib might work.