This swap sounds like fun! I am an international swapper so as long as the box isn't TOO big or heavy (or if a fellow aussie signed up!) I would definitely be interested. My work is closing down for renovations for most of August, so I will have plenty of time to craft.
I just remembered the time I stuffed a very 1970's three piece suit and a dress shirt in a Trivial Pursuit box to ship to my cousin for a costume party. And the time I shipped a couple cassette tapes to a friend but only had a shoebox, so I filled the box with all sorts of random goodies and fun stuff. Suddenly the inner box-stuffer in me got VERY excited about this!
I am just the same. One of the best gifts I had ever received was when my best friend and I were living in different cities she mailed me an 'Easter egg hunt' a huge box full of packing peanuts and confetti with a dozen little easter eggs hidden throughout.