What I mean is something like this.
00:00 blue_tetris chases 29403 down a long corridor on finding out that he's last in RTaB.
00:01 Tunco123 goes to the bathroom.
00:02 Unreality announces that he's integrated mods into Ned, starting with changing gravity strength.
00:03 kkstrong is the first to grab a computer and load up N, in order to mess with the gravity mod.
00:04 kkstrong accidentally presses the button to reverse gravity direction.
00:05 Unreality realises what he's done and tries to undo it while the computer and all the forum members slowly drift towards the ceiling.
00:06 Unreality returns gravity to normal (CLUNK!) and starts to try to strangle kkstrong Homer Simpson-style but can't find him.
00:07 Tunco123 returns from the bathroom and complains that the water in the toilet was moving in a strange way (i.e. upwards) when he was in the bathroom. "What happened?" he says. Nobody says anything.
etc.
No time travel; no killing forum members; no double posting; no non-forum members can enter the place.