Just something I added to my copy of IC2 which I find handy is being able to right-click a chest item in my hand and have it swap out with my current chest item.
eg.
Bat-pack equipped, Jet-pack in hand.
When I right-click with the Jet-pack it should swap with my Bat-pack leaving me with the Bat-pack in hand and Jet-pack equipped.
Items to be swapped:
-Bat-pack
-Jet-packs, both.
-Perhaps Nano/Quantum chest armors.
Bound to be something wrong with this since I coded it while sober >.>
Code
public ItemStack onItemRightClick(ItemStack itemstack, World world, EntityPlayer entityplayer){
ItemStack tmp = entityplayer.inventory.armorInventory[2];
entityplayer.inventory.mainInventory[entityplayer.inventory.currentItem] = tmp;
entityplayer.inventory.armorInventory[2] = itemstack;
return itemstack;
}