That ability to extend / create custom macro's would be invaliuble - kinda like a plugin / extension system.

It could either be through loading a JAR file of classes extending a common interface or base class, or through bsh/scrappy code, or perhaps some other scripting language. I prefer the idea of dumping JAR files into a "macros" directory inside confluence (or an external lib directory being set to from confluence administration) as then it would allow the macro writer to do pretty much anything.

The possibilities are endless. We could integrate our confluence install with our custom intranet scripts (parsing the output and giving a more accurate output). We could get it so that it could parse the xml files our applications provide for documentation so that the documentation could seamlessly be integrated into confluence. We could get our IT support space to probe / parse the bind config files and list the current IP assignments. We could display the NOCOL information for our network system / uptime so dumb users can still obtain useful information without getting confused.

This is possible to a limited extent through include files - but macros would be so much better and avoid the need of portal scripts running on webservers.