The threads where dozens of knowledgeable respondents are in consensus, but the OP is still fishing for the feedback he/she would prefer to hear.
As a moderator, these are my favorite ones to close. 
My Grandfather worked for (HYPSM, etc…) when he got out of the Army after the Korean War. He even has a plaque commemorating him on five years of service in Physical Engineering.
Does that make me a legacy and will it make up for my bad SAT scores?
Lots of threads lately where the first timer knows holistic is really all about stats.
And where posters throw out lots of college suggestions based on…an ACT composite or SAT total and GPA, with no breakdown, nothing about major, prefs, or ECs.
Threads where it is recommended the kid take the SATIIs which are only required by two handfuls of the thousands of colleges AND it is clear the the kid is not heading toward any of those twenty colleges.
Threads where the blind lead the blind.
Respondents with absolutely no experience in the topic confidently advise others.
^Income tax questions
^ I was thinking more along the lines of “I have no idea whether or not my essay is any good. Could you read mine, and I’ll read yours??”
Ones where respondents represent themselves as experts regarding every college or university in the U.S. when in actuality they’ve rarely visited more than a handful of schools and their experience consists of an extensive Google search.
Threads where the poster in fact needs specific financial or legal advice that random folks living in different locales can’t provide, no way no how.
The threads where a poster w a post count of 1 declares he/she is a HYPMS student and is now the expert of everything.
The posts where the OP wants to narrow their list and multiple posters suggest more schools.
Ones that are so long you know that no matter what you post it has already been said. Either that, or it has just become an almost private thread between a dozen or so posters.
A dozen? More likely 3 or 4.
Hahaha, yeah.
The rich kid FA entitlement rant threads.
Does any one of them top the epic thread where $350k family income isn’t enough to keep up with the high cost of maintaining a moldy 2 million dollar house, a second home in LA, 5 cars, tutor, fitness classes, foie gras, sashimi grade fish, lululemon and prada?
The thread where posters take the opportunity to brag about their child. I love to hear kids’ stats, but not when they don’t add to the conversation. Even worse? When they list the ECs.
replies that respond to someone without a post number or quoting the person…(I’m I suppose to remember what every responder said!?)
@ClaremontMom, I think it’s inconsiderate to do anything but quote the post. Sometimes the referenced post number is so far back, it’s difficult to find. And the reader just shouldn’t have to do that. I miss the quote button we used to have.
I agree, I prefer the quote but I’ll take what I can get. The only exception would be this one where I’m responding to the post right before mine.