Too common! I have (or had?) a few stacks and have no idea what it's good forOne of the UE mods (I think it's Mekanism) adds osmium. It's actually surprisingly common!
My latest mod idea:
EnderFriends:
Give a few Eyes of Ender to an Enderman to befriend him. Then you can:
* give him a chest and then rightclick him to access it. You can have him follow you around, and even pick up your stuff when you die
* give him a crafting table and teach him to craft stuff
* give him a hoe and stuff to plant
* give him a sword...
* get him to move a mountain, or construct a wall
So basically a mix between golems and turtles. And if Endermen are too tall for your needs you can get Enderbabies...