The Gamma Ray Quantum Particle Disentanglement Apparatus (GRQPDA) is a feature of the Everything2 XMPP Transport that has a really cool name and yet does nothing. No, seriously, it actually does nothing. You know how submarines will drop to the ocean floor, shut down their motors, and just sit there? Yep, that's pretty much how the GRQPDA works.
Alright, so now you know what it does, (Admit it, you don't do you?) you're probably wonder what the GRQPDA achieves. Well, basically it allows me, or any other potential user of the Everything2 XMPP Transport (E2XT), to become like Schrödinger's Cat, Schrödinger's Scout as it were in my case, in that they are here and not here at the same time. Wait, what? This must be getting incredibly confusing by now. Yes, I tend to get like that. With the GRQPDA turned on, a user can disappear, leaving no trace they are interacting with the site. This is done by, as I said, ceasing all activity which draws attention to yourself. E2 Staff and users of Level 10 or higher have the ability to cloak themselves officially. Good for them, this is for the rest of us. Of the various methods of hiding from the site, it's not easy for to un-officially cloak effectively, not at time of writing anyway. It can be sometimes be useful however when one leaves their computer on the site and goes AFK, but doesn't want people talking to them in the catbox and wondering where they are. When accessing E2 via the E2XT, here's what you'll see:
"Normal" user - Appears in list of Other Users with a times of last seen, last spoke in catbox, last /msg'ed you, last noded, etc tracked properly.
Manually cloaking user - Keeps appearing and disappearing from the Other Users list, time last seen will likely be inaccurate.
Officially cloaked user - Same as normal user, officially not with accurate last seen times in the Other Users list.
GRQPDA user - Last seen time is whenever they last accessed the site without the GRQPDA, whether they've talked in the catbox since then or not, using the XMPP "Invisible" mode in combination with the GRQPDA makes these users virtually undetectable.