prototype for a 1 byte interdimensional wire i put together on the redstone server
from right to left:
1. push one of 8 buttons, dispensing an item into the water stream
2. the item is then transported up an item elevator -- or, if we're sending signals through the nether, through a portal
3. once through the portal, the item is handled by an item sorter
4. the item sorter sets up a serial encoder to send the signal along a single wire
5. the redstone signal travels along the wire -- hopefully in the nether -- to save on costs
6. the signal reaches the decoder and is split into 8 wires again
7. optional postprocessing allows the signal to be saved in memory, and also output a short pulse
of course if this was an overworld -> nether -> overworld wire, step 7 would be dispensing an item so that it could be sent back into the overworld, through another item filter, until we finally get 8 output wires.
not pictured are the chunk loading infrastructure you'd need on both ends of the system
the use case i'm planning for this of course is to hook them up to my pearl teleport system