Two thoughts:

When I was in university I had a roommate who liked to experiment with
sending things in the main in the wierdest way possible, to see if they would
get through. He'd heard that Canada Post MUST deliver a package as long as
the package has sufficient postage attached!
Two of my favorites were:
1. He dried a loaf of bread, hollowed out the center like a box, put what
he was sending inside, wrapped it in string, and applied a postage stamp.
2. Being at a marine biology field station, we had access to lots of clams.
He used a very large Tresus capax (or nuttallii?), simply wrapped in string
with an attached stamp!
Both of these packages got to thier destination, or so I'm told.

My least favorite packing material for shells:
NEWS PRINT ! Yuck! Your hands get covered in ink and so might the shell.
My favorites are toilet paper and ziplock bags, the TP to protect the delicate
shell, and the bag to keep everything in place.

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Peter Egerton, Vancouver, Canada
Collector of worldwide Mollusca
http://www.intergate.bc.ca/personal/seashell/index.html
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