I have a very distinct memory of a graphical BBS that ran on the Apple II in the late 80s. It's possible it only ran on the IIGS, but I don't think so. I think it used hires mode. My memory is that it was called gbbs, for graphical bbs.

There was something called Greg's BBS, but that's not what I'm referring to.

If such a thing ever existed, I can find no trace of it on the Internet. :-(