Here's a nice idea that came to mind recently. Basically, it's a sort of postbox where people can leave messages addressed to other players. The message appears as soon as a player with a specific name enters the server.

It could be used to say at what time players should meet up for example. It could also be used by admins to leave warning messages to any problematic players.

At the moment, to post a message for your friend, you must say "mail <nick> <message>". To read any messages left for you, you must type just "mail". (You can alternatively type "mutate mail ..." in the console.)

One problem is how to match up the recipient <nick> against real players, since some players' nicks are hard to type in the console/say? At the moment it strips all non-alphanumeric characters, then capitalises, before comparing the posted nick against each player's nick. So to send a mail to "F0X|nogginBasher" you could type "mail f0xnogginbasher hi" or "mail =f0x~!~Noggin.Basher+ hello", but "mail nogginBasher " will not work. Any thoughts on improving this approach?

Another todo, is to lookout for when a player joins the server, and when they do, inform them if they have new mail in their postbox. At the moment, they must say "mail" before any checking is done.

There is also the "privacy" issue of players with similar nicks accidentally reading (or just clearing) each others postboxes! But to fix that would require logins and other such complications.

Another simple mutator I just finished, publishes the game's teamscore and time remaining in the server's title. (I saw that on an AS server, and stole the idea.) You can see it in action on 213.121.244.94, once a game has started.

Btw, players and spectators can also use mutate commands to call the mutator, for example: "mutate mail ..." and "mutate read ...".