What are the most useless thing in heaven?   

Absolutely Nothing. Everything God has there is useful..It's while we are on Earth that we have things that are not useful...Lori

I would think in heaven there would be no useless things and we would see the purpose of everything...in my perception of the afterlife at least!

I dont think that heaven exists
But thats not really what I wanted to say.
What I would like to ask is what exactly was your thinking when asking this question?
I think its the weirdest question I have seen on here.
But you know what,I actually quite like it.
Its original
Its refreshing
I will even say this much,surely nothing in heaven will be useless,will it?
I dont suppose any of us will ever find out,cos no one has ever come back and confirmed heaven even exists
Well,maybe jesus did!!!

Well I'm thinking that if we don't need it then it won't be in Heaven. But a few things that we have here that would be useless in Heaven would be medicine, antiaging products, vitamins, anything health related.

Lawyers! Ha, ha!

I can't think of any. Based on the Scriptures, everything God created is very good (Genesis 1:31) and we are realizing now each of them that He created has purpose for our own good. Only man made things can be useless or seemingly useless but the end may be destruction just like nuclear bombs.

Sin?

I don't know. Are there even material things in heaven? As far as I know, as what I believed, in heaven there's no hunger, or sadness, or illness, or boredom. What do we need anything for?

And I won't even care about material things. What's important is that we're in heaven, we're with God.

that is a strange question and I would not know how to answer that. My idea of heaven is that it is the most magnificent place and therefore I could not think of anything that is useless, I sure hope it has all my dogs and cats.

everything that you've accumulated on this earth will be useless in heaven, but everything that is in heaven will be useful. heaven is a great place and there is nothing but good there. material things on this earth aren't gonna matter one bit once you get to heaven. you can't take them with you. God bless