Can be anything from any source, movies, books, comics, video games, manga, anime etc.
Pic related is mine, the dragonslayer from berserk. I like it because it's simple. It's just a big fucking sword, no fancy bells and whistles like enchantments or spells.
Second runner-up is sting from lord of the rings, I like that it glows blue when orcs are around and it can be used in the dark as a light source.
"Favorite" is a strong word, but I really like the caber from Beastmaster.
It looks like something impractical that some artist would draw, but then it turns out it's pretty similar to throwing weapons that certain African tribes used
In the real one the purpose of the shape is to ensure that a sharp part of the weapon always hits your target, IDK if the movie prop would function that way but it certainly evokes the same feeling when I look at it.
I like it