Can anyone offer any suggestions for setting up a very simple lobby server? (Documentation or some sample code) I was just hoping to find a very simple PHP script or something that would assist me in handling the backend matchmaking work.

I have written one in C# which lets you start and join games, and chat while you waint for the game to start. It's a bit overengineered for what you want, though, and I don't want to release it just yet anyway. But I might be able to answer questions about design or whatever.

Thanks. How do your clients find each other?

I'll be using VB/.Net on the clients... I have a hosted server and I was intending on using it to help each of my clients "discover" each other. After that, the server wouldn't really be involved. What I was hoping to find was an example script (Perl, PHP, whatever... just not ASP.NET) that I could run on my server.

The AP (who is not me, by the way) sets out the basic points really nicely. My implementation differs in that the clients remain connected to the lobby server while playing the game(s), and all their communication is passed through the server. This is suitable for 'minigames' (for example, my test game is a bridge game), allowing clients to be playing more than one game at once and avoiding any problems with NAT, but adding lag and bandwidth use on the server. This also lets you run serverside games, such as those that require persistent worlds.

So in answer to your question, clients find each other because they are both connected to the same lobby server at the same time. One of the events the server sends to clients is a list of clients currently connected.