History
Back in ye olden days of peer-to-peer file sharing, there was a program/network called Gnutella (launched in 2000 by the folks of Winamp fame). The network was probably better know by another name, taken from its later and most famous/infamous client LimeWire.
Initially, search on this network propogated from node to node. Each node that got a search request either (a) responded with a result, or (b) decremented the TTL and forwarded the request to all of its peers. Horribly inefficient. Though one side effect of this inefficiency was many people’s searches would flow through your node (i.e. your desktop computer).
Watching the Flow
An implication of all the searches flowing through your node was that searches were anything but private. Most clients kept this detail hidden and left it all as an implementation detail. Some clients, though, had a UI page to show all these searches that were flowing through. This meant that you could see what others were searching for (though not necessarily who was searching, just that a search request got forward to you from at least one of the many many peers your node was connected to).
Aside: if you were ever curious how depraved some folks are, this certainly satisfied that curiosity (in a sometimes traumatising way).
Now, if all the search text is flowing through your node, that means you could then issue your own search that would flow through all the other (nearby) nodes. Boom! Two-way text strings between nodes. That’s basically a chat system!
Chatting
Learning this fact, some friends and I actually used this search system to chat with each other. Not about anything serious (we were teens after all 😂). Actually, IIRC, most of the time we were already chatting through some other (actual purpose-built) chat system, and were mostly just amusing ourselves. We’d post our bullshit out into the void and make random snarky comments about other people’s searches that we saw flowing by.
The most fun part was just knowing we were using the system to do something it wasn’t intended for. That’s how we knew we were 1337 😄
