From the olden times I remember when you were granted gold per word you typed (to a maximum amount per post) and that the CB used to be filled with people page stretching by posting only "spam spam spam spam spam" over and over again to get gold xd I don't miss it.
I remember that little theater we had before where you watch sponsor trailer and get items or gold. The only thing we have to remember it by is one of the music tracks in the Aquariums.
Speaking of Aquariums, I think it used to have a little message in a bottle thingy there where you post something and it arrives in somebody else's aquarium. I didn't like it much because it filled my aquarium with comments.
I kind of miss how hard it was to get gold in the first place. Now it's so easy with the Cash Shop and stuff and there were less rare items that made them more special. Like the panda hat, devils tail and the OMG hat were such a big deal.
I tend to remember the Cinemas - in particular, the educational films they showed there. They were wonderfully awful in their own ways, haha, and the ability to chuck tomatoes and popcorn at the screen helped the entertainment value.
Whenever Halloween rolls around and the NPC costumes are updated, there's a welcome wave of nostalgia. Just remembering the costumes over the years, including Agatha's terrifying one.