you know, i dont think of it as a "fun" question, but an interesting question, but not a dumb question... some of you seriously need to lay off with your hostility to the guy. it's a genuine question, and im kinda curious myself...
when it comes to the Bible, it never says whether there will be sex in heaven or not, so i dont know...
having said that, we have not even seen nor heard the things that go on in heaven... personally, seeing how love is personified in the Bible, sex will more than likely be obsolete. while sex here on earth feels good, and is a gift from God for married couples, it's finite, since it's the flesh.
every form of love that we experience on this earth is a foreshadow of the infinite, and greater love that the Father has for us... so when we see someone, and we hug, or embrace someone in heaven, the love that we will express to one another will be greater, deeper, more intimate, and more beautiful than anything sex can express, because all of us will be complete in every single form. I know thats really hard to understand because of how we view sex... believe me, it's hard for me to understand, especially being close to marriage... but thats whats been put on my heart.
that's my 2 cents