We've just launched the open beta for Adventurize, which is a new advertising platform for Minecraft that allows advertisers to display ads on servers through a plugin. The website is built with MeteorJS, and is currently open for server owners only during the 1-2 month testing period.
You can read more in the official launch post: http://www.minecraftforum.net/topic/1874092-adventurize-laun...