Bukkit

Currently Courier will use one new UID for each new message up until the limit of 32766 is reached and then no new Letters can be created. I don't think that will happen in the near term, but if you run an immensely busy server you might want to use the Economy support to make sure it doesn't.

Anyway, I'm going to add something along these lines (and please comment on this ticket with your own ideas on the subject)

/courier delete

Deletes the letter currently held in hand. There will also be some more immersive in-game ways of doing this (throwing letters in fires, burning them in furnaces etc)

/courier storage (op only)

Will display the number of letters currently stored, and the amount left until "full" (no more UIDs)

/courier delete [playername] (op only)

Deletes all letters 'owned' by playername. Useful when banning a user, someones quits playing completely etc

/courier recycle [age] (op only)

Deletes all letters created before the specified time period. Not sure how the time will be expressed yet. Hard dates are not as user friendly, "2 weeks", "6 months" etc are.