The juggling community has something called juggler mail that is effective and relies on the fact that jugglers get together regularly for conventions around the country (and world, in fact) throughout the year.
If an item isn't urgent then it's taken to a convention and passed on to someone who's going in the general direction I want the item to go. They then travel to another convention or meet up with friends and the item is passed on again. Obviously it relies on trust, but I've helped pass on a variety of items including an ice axe and books. I've had a ruck sack returned to me from London via York and Durham.
For fun we set up a small stuffed bear complete with disposable camera and it was dropped off at a New Zealand juggling club. There was a message inside and a website for updates. We asked that the bear make it's way back to Bristol 12 months later and it did, although after travelling half way round the world he somehow managed to get lost in Bristol!
