With the Empty Space mod you can travel to a new 'empty' dimension, that you and all other players can use for storage systems, farms and other cool things that don't fit in the overworld. To get in this new dimension you need to have a Telepearl. For the Telepearl is a special item needed, called: "Interdimensional Ender Shard". You can find this shard inside a ancient shard room in the new forrest biom.
!DISCLAMER! This mod is still in alpha and probaply has lots of bugs to fix