@BleurghUna
Is it deliberate? I thought it was a typo.
SPLUTTER of outrage of hte very suggestion of a typo 
Hello and sorry to be a bit late to this but I can quote Justine on this:
Back in the dim and distant past there was a big hoohah when we first introduced chat. Folks thought it would lower the tone and Last Day (not last 15 mins in those day) was very popular. Many didn't want to scroll through a load of chat threads at the top of Last Day before getting to other topics so we called it _chat and that way chat threads came at the bottom of the list.
Hope this helps
NB I shall now move this thread to Site Stuff where it rightfully belongs.
Thanks