Amy Alkon, a syndicated advice columnist and self-described “manners psycho,” certainly thinks so. Just ask “Barry,” a loud cellphone talker she encountered recently at a Starbucks in Santa Monica, Calif.

“He just blatantly took over the whole place with his conversation, streaming his dull life into everybody’s brain,” Ms. Alkon recalled in a telephone interview.

Among the personal details Barry shared that day — errands to run, plans for the evening — was his phone number, which Ms. Alkon jotted down.

“I called him that night and said, ‘Just calling to let you know, Barry, that if you’d like your private life to remain private, you might want to be a little more considerate next time,’ “ she said.

So there.

These days it seems that as the rudes have gotten ruder — abetted by BlackBerries, cellphones and MP3 players — the scolds have gotten scoldier. True, many people have grown complacent about having to endure others’ musical tastes or conversations — or more accurately, half of their conversations. But among the disapprovers, withering glances and artfully worded comments have given way to pranks and other creative kinds of revenge…