Legolas and Gimli headcannon
So I have this theory that Legolas and Gimli end up in the fellowship together and actually figure out pretty quickly that they like each other (cause, ya know, neither of them are exactly subtle™). But they also decide that they must keep it a deep secret, no one can know, or else both their families will be dishonored or something, and it's all very solum and all.
But the thing is, they are not great at keeping it a secret. They'll both claim to hate the other, and then mysteriously end up taking every opportunity to have some time alone together. Legolas announces that he's going double back to make sure nothing's following them, and suddenly Gimli saw some rock he's going to stay and take a look at. Subtle.
The rest of the fellowship, completely confused, comes to the conclusion that Gimli is trying to flirt with Legolas, who wants nothing to do with it. (Merry and Pippin*accidentally* walked in on the pair flirting, and have been sworn to dubious secrecy)
Shortly after Loth Lorien, Legolas and Gimli stage a dramatic scene in which they reveal their relationship, to the complete confusion of the rest of the fellowship, while Merry and Pippin do their best not to explode with laughter.