An international network of/for intelligent organisms
It grows very slowly, but it must communicate with electric waves faster than it grows. How much faster? Can we communicate with it as waves as fast as Humans think? Even if nobody has found meaningful patterns in the faster electric waves, just their existence would be enough for me to try. In the usb device containing living slime that communicates with the computer through electric input and output, what is the update speed?
Also, have there been any objections to large scale growth of the slime so multiple computers and people could hook into the same slime from their different computers and buildings? This is only relevant if it can communicate, however stupidly or randomly, at our speed. It may be a useful addition to the Internet. We could hook certain locations of it's electric input and output to an Internet address. If its worth talking to.
In its growing shapes, it demonstrated optimization of npcomplete math. If it can do that in its realtime electric behaviors, or if it can learn, this could work.
I dont think its going to learn our language or talk advanced math to us, but it may be a good electric field to connect to other things, like holding your hand above it and moving your fingers it may feel that and you may feel its electric changes?
I've hooked one up to an electrophysiology rig before. The signal is incredibly weak - you need a decent amplifier and a faraday cage but you can pick up an oscillating signal that follows the pulsing of the plasmodia - when I say weak, someone with long hair nearby causes enough static to swamp it...
I don't think the electrical signal is that relevant - I think it's incidental to the movement of ions across the membrane of the organism ( which I suppose is an electrical signal if you get picky.. ).
As for growing a big one, your biggest problem is keeping humidity high enough - I've got them up to half a square metre, at that point I serious doubt there's any meaningful communication from the furthest sides of the plasmodium - it tends to fragment and wander off in different directions, usually ending up under the sofa, on the stereo or anywhere else I don't want it before it dries out.