You can now use the chat command /buzz allowed by playername, to acoustically and visually notify an other player that is online in the same location.
For those of you that remember what buzz was.
While this might be considered a violation pf privacy, according to our modern and skewed sensibilities, i will not add a way to block such actions.. yet. I believe that if someone is annoying you because its using buzz excessively on you, you should talk to that person, and even report it as abuse, and we shall see from there what to do. Right now i don't believe buzz will cause any trouble , and you can always use /shut up chat command if someone is annoying you.