Clearly it’s common courtesy (and standard practice) when referring to a member to give his username exactly as he or she does. For instance, if they don’t use a capital for the first letter, then don’t foist one on them.
But how if such a username is the first word in a sentence? Does grammar bow to etiquette, or does etiquette give way to grammar? (And yes, I know that the dilemma could be simply avoided by shuffling the sentence around, but, with respect, that’s not the point.)
This question applies not only to usernames but to things like iPod, pH, etc. when they begin a sentence. Also abbreviations like Kbps vs kbps - these have two distinct meanings and capitalizing the latter would change it’s meaning. Grammatically speaking, there is no such thing as a non-capitalized proper noun, so I’m not sure the question can be answered because it isn’t a valid question if it includes accepting the existence of a non-capitalized proper noun. The rules of grammar have to catch up with the internet age. Personally, I would leave it as is, or rearrange the sentence so that it isn’t the first word.
This isn’t related to grammar. It deals with orthography, or how the language is expressed in writing.
And there’s no law in stone that proper nouns have to be capitalized. We can change the convention as we see fit to deal with the new age. Personally, I leave the lowercase names as they are.
Sorry for the error in terminology but the point is the same. English language orthography dictates that every proper noun be capitalized. No it is not carved in stone but it is universally agreed upon in all English language style guides. While they contradict each other in other areas this point is universally agreed upon by them all, so far as I know. So you can’t ask the question ‘how do I handle a non-capitalized proper noun if it begins a sentence’ because there is technically no such thing.
(covers eyes)
I deduce that the OP has a username that begins with a lower-case letter. (Otherwise there would be no discussion.)
(uncovers eyes)
Hey! I’m Sherlock Holmes! 
I don’t think it matters. Yes, every sentence in the English language should start with a capital letter, but yes, the language changes. e e cummings probably had the same problem, as do people writing about his poetry. Seems to me that one would not capitalize his “e” at the beginning of a sentence either.
We’ve tried to hold down playing games with other posters’ names (it was used as a form of snide personal insult), but I don’t think anyone would consider that capitalizing their name was an insult.
Newspaper style guides tend to have to tackle issues such as ‘eBay’, for example here:
It seems to me (although I don’t have time right now to try to find any examples) that I’ve seen people capitalize other poster’s names even when they’re not at the beginning of a sentence, without the poster referred to getting upset about it. I can’t speak for anyone else, but I suspect it may be from force of habit more than anything else; a name is considered a proper noun, and thus always capitalized.
One time in past for just that reason (force of habit) I inadvertently capitalized the first letter of a username that was all lowercase and promptly got flamed for it by the person.
I’ve forgotten what that username was, as the person changed to a different one at a later time.
Urban legend alert: The funky caps (or lack thereof) were neither his idea nor his preference.
I first remember this coming up when Jerald terHorst became Ford’s press secretary. He made it clear that it was lower-case “t” in all contexts.
I have no idea where the idea arose that it was okay to change capitalization purely on location within a sentence. And re-arranging sentences order to avoid it is just plain clumsy. terHorst had it right*.
(“Right was terHosrt.” “It was right to terHorst.” “The person who had it right was terHorst.” umm…)
I capitalize the username if it appears at the beginning of a sentence because the capital letter is an important part of the signal that one sentence is ending and a new one is beginning. Nobody has ever said that they object to this.
A good illustration of what I’ve been doing would be found in a sentence where I list a number of members: “Aldiboronti, glee, and ftg have posted in this thread.” If I wanted to include Scarlett67 in my list, I’d just put her first and avoid the whole problem.
If I were to run into one of the rare cases where the capital letter would fundamentally change the meaning of the word, I’d shuffle the sentence around. But it’s not really feasible to do that in all cases in this age of lower-case proper nouns.
This is a case of two long-standing principles running head-first into each other. The first is that proper grammar increases the clarity of writing. The second is that you should call people what they want to be called. While the second almost always trumps all others considerations with regard to social conventions, I’m not sure it trumps all grammatical considerations.
Ultimately, I’ll go along with whatever is chosen as proper usage.
Aldiboronti, please tell us how you feel about it.
In referring to others, uncertain, hence the question (although admittedly the problem rarely arises). When it comes to myself, and others referring to me, indifferent.
I think of names as being not “words” but as “items” … changing the capitalization or lack of capitalization is akin to changing what’s inside a quote.
So would it be proper to write “[A]ldiboronti, glee, and ftg have posted in this thread”?
Well, if we were talking about formal usage, there are two principles here.
The rule that the first word of a sentence is capitalized.
Deliberately irregular non-capitalization of a proper name.
The question is whether a standard rule should be over-ruled by an irregular and non-standard practice. My inclination would be first, to rephrase the sentence to avoid the conflict. If that were impossible, I would probably consider that the standard practice of capitalization of the first word of a sentence should override the non-standard captilization of the proper name.
However, since this is message board, and communication is informal, I would say that non-capitilization is fine.
Actually, the best rationale for always spelling a username exactly as it occurs is so that a search on “exact name” will find all instances.
On the subject of etiquette, what about usernames with numbers in them? While I typically copy/paste (more because I’m an atrocious spller and want to be sure I get the name right), and there are plenty of names where the number is an integral part, I often find the number a bit … bit … dehumanizing?
Not in every context, surely not when quoting:
or when referring to a post:
As Scarlett67 pointed out, George Clinton wore funky caps.
But when posting to (the online equivalent of talking to?) someone, I find using numbers to be jarring:
Thanks for posting that link Scarlett, I always took it for granted that it was his idea.
Rhythm
(this thread got me to thinking about how I parse my own nick. Rhythm Devils = RhythmDvl = Rhythmdvl. Whenever I informally refer to myself it’s Rhythm, but there’s Mrs. Dvl, The Dvlcats, the Dvl Household, etc. Odd.)
Interesting about E.E. Cummings, Scarlett67, thanks.
From an Official point of view in terms of boards administration: we don’t want people playing deliberately insulting games with usernames. However, we don’t care about other situations – capitalizations, etc.
Seems to me that flaming someone for a simple mis-spelling or typo or capitalization is pretty much the stuff of which drama queens are made (not that we’re short on that here.) A simple post asking to please use lowercase would be more effective and more polite.
So, basically, I guess I’m saying that it’s not a thing mods will care about.
That was precisely my reaction when I was flamed.