reply to post by noconsequence
Its happened to me more then once, what really makes me go "ahhh" is when I type out a 4000 character reply and hit submit, to get the 404 error.
now that's a bummer moment

Try to preform a search on the topic of whatever you were reading, maybe someone has posted something similar to it, it could have been a duplicate
thread, which would explain it being moved to the trash bin, you may luck out.