You have discovered a way to harness the power of an ender pearl and enhance it to allow for long distance and even cross dimensional teleportation.
To use a TelePack, simply set a location by crouch-right clicking then set out on an adventure.
When you're ready to return to the set location, just hold right cllick to charge up the pack and teleport back to the saved location!
If you'd like to teleport across dimensions, simply upgrade your TelePack and you'll be crossing the dimensional gap in no time.
TelePacks come in two different forms, Basic and Advanced. Basic TelePacks can only travel in the same dimension.
And TelePacks come in all 16 of your favorite dye colors!