What the heck is a farfoos?
A made up word. Like mimkrys, onideus, flonk, soppled, smunged, borked, plonk, joo, lits, chix0r, froup, nyme, etc. Some of them are derived when a kook makes a funny spelling mistake. Like Russell's most recent "bamboon", that's a perfect example. It gets picked up and then circulated often as a means of immortalizing their kookish behavior.
Some of them were also originally meant to convey sounds or actions, like murmle(s) and smep(s), although some of them were later co-opted to mean different things (mostly by confused people trying to decipher nonexistent meaning). Like smep(s) originally meant a short, quick, affectionate little kiss, but later got bastardized as the acronym "sperm meets egg plan".
They're handy to use as markers for the purpose of tagging and searching for material later on.
For example if I make up a brand new word right now, like veernaynt, I can now use that word to find this particular post in Google at any time in the future.
We used to use them a lot on Usenet as x-headers. Basically you could make up a unique x-header and then use it to determine forgeries or find particular posts.
We used to use a lot of other tricks too, like ROT13 encoding in order to obfuscate information and posts from n00bs. So we could have conversations back and forth about people but they weren't able to read any of it (unless they knew what encoding scheme we were using).
That's likely going to start trending again here soon, as social media sites like Twitter crack down more and more. If all the anti-SJWs suddenly start actively encoding their tweets... the dumbfuck SJWs won't be able to read it and, even fi they can, they won't be able to report it, because the automated abuse filters won't be able to understand any of it.