Ooh, yeah. It could all be in a tower, each floor is a different section, and different rooms are different topics.
You wouldn't have to walk around the building to enter different sections or rooms, but you can. Each person has a device on thier wrist they can use to teleport themselves to different places in the building, although that kind of defeats the purpose of being able to walk around the building... Dangit now I really want to start on this, but I know i'm too busy to take on another project.
- People would be able to select from a large library of pre-made character sprites, or add their own.
- A global IRC style chat.
- You can see other people moving around the building, and can always send private messages, but there are designated areas where you can chat with text bubbles above your heads. (can't chat everywhere so that posting in topics doesn't become useless)
- You can paste images on the inside of topic rooms (not uploaded from computer, hosted somewhere on internet)
Posting messages in rooms Hmm... I'm not sure how you would handle that, maybe something like a guest book, or sticky notes on the wall.
You would enter different floors of the building at a corner, and the hallways would be arranged something like this
|-------- |
| --------|
|-------- |
each hall is like a page of topics. The ones with the newest posts are closer to the entrance of that floor of the building.
Anyway, thats my idea of how it would work. I should probably get out of here before I become too excited and start it as another project... I have too many already.
EDIT:
Ah, I didn't realize how long it had been since this topic had been last posted in, the idea excited me so much that I just had to say something about it. Sorry.