There are currently two methods a player can use to report something in-game.

/emergency

This sends an email to me along with your current location on the server. It should only be used for things that need instant attention such as verbal abuse, racism, spam, etc.

/pulser report

This can be used to report a redstone pulser. It can also be used to report gigantic lava-falls or other structures that are not allowed on the server.

Yea..