My friend and I have two servers, one for his family and one for mine. We would like the chats to work between the two. Is there a plugin for this? I couldn't find one, but I'm really bad at searching.
Set up an IRC and use http://dev.bukkit.org/bukkit-plugins/craftirc/ I know, its complicated but it's the easiest way right now.
Actually, no. xServerChat here: https://github.com/Double0negative/xServerChat/tree/master/out/ is the easiest way currently. Use the xServerChat.jar and click Raw to download it.