speaking of "the uselessness of the uselessness of [grammar/punctuation rule here] online," I have discovered, as I do much more writing in forums, etc., and composing as I type, that I am *very* likely to close my quote, and then decide I want to continue or end my sentence.
Which leads me to spontaneously use the British style of periods or commas outside quotes.
It has amazed me, how often I do this sort of thing:
Just say "cheese", and I'll take the picture.
I end up doing the same thing, and it irks me to no end because I much prefer the American system, the pro-British advocacy of Language Log notwithstanding.