First of all, my idea serves no useful purpose, except something like trolling, but nevertheless, it seems fun. Little background: I was a main admin in the server A, but got kicked out due to feuds with the owner. I made my server B, and intend to surpass them. What my idea consists of: To broadcast every x minutes something like: "We are [B-A] players ahead of A." of course only when in the lead. Is it possible, could it be done?
I think this could only be done if the other server had the plugin too. Even then, it would require getting and setting values on the internet, and it would be very complicated.
The player count actually would be easy, but as Freelix mentions there would be no way to broadcast on a separate server unless they were also running the code.
This actually couldn't be that hard to code. All you would have to do is ping the server, and see how many players are on it. Since default MC can do this by adding servers it shouldn't be to hard to incorporate into bukkit.
When I wrote that I didn't fully write it correctly. I meant just pinging the server to see how many players are on. :/
If a server could be queried by just a simple php script, why not implement it in a plugin? I have no actual knowledge of bukkit internal mechanics, but if votifier can be made, the one above sounds reasonable, right?
You didn't read the second part of his request.. He's asking to send chat messages to other servers. You can't do that unless you send the message as a player or the other server has a plugin to accept the data (msg).