today i mailed three packages that were not precisely flat. one work had a small plastic child's ring attached to it, another contained the wrapper from an eyeshadow package that was re-filled with paper, and the last was a piece of stiff paper that had been folded into a triangle shape.
after being questioned about the contents and their value, i still had to fill out a customs form (i think there may have been a fee in the total, but i didn't get a breakdown) for the ring and the eyeshadow. they let the folded paper pass without customs after i demonstrated the folding with a piece of scrap paper.
in the future, i think i'll stay within the bounds of flat paper unless i'm prepared for snafu. i also wonder if the reverse will apply - if someone sends mailart with irregular shapes/attachments, will it be questioned by customs on the Chinese end (would the artist in China never receive it, or have to pay a customs tariff)?
has anyone tried sending unusual items in envelopes to China? another experiment may be in order!