Here's a concept that I wanted to work on for an upcoming forum I am working on. Sadly I doubt I'll have time, but wanted to at least show it here for inspiration for anyone who's interested.
I generally like the look and feel of NodeBB but I wanted something a little more dark but also modern (which usually doesn't go hand in hand) for this theme. There's nothing special really in this theme in terms of added functionality.
It has the basic categories and their description. The avatars are the users who've posted there most recently. I had an idea that when you mouseover their avatar it would give a little snippet of what they said, and give the option to view user or view their post specifically.
Other than that, it's pretty basic. Thought I'd share.