And, as promised before, some more on mailing your quilt - now that we have some completed ones, I thought it was time for this!
You are not required to send any extras with your quilt, but if you do, please bear in mind customs issues if posting internationally. As mentioned before, some countries are stricter than others about what can safely pass through customs - this is particularly true with food and agricultural materials. Usually a bar of chocolate or a box of tea is ok, but just worth being careful if you are not sure - for instance, whatever you do, don't send any plant material or seeds to Australia, or your partner might never get her quilt!
And another note for those sending internationally, many countries have limits as to the value of items that people can receive as a gift before having to pay a customs charge on the item - for instance, in the UK, anything which is valued at more than £17 (which is about $35US at the moment) will incur VAT & customs and a postal surcharge. So while I know your work is valuable, unless you are actually paying to insure your item in the post, it's worth keeping the value a little low on the customs tag so the recipient doesn't have to pay a charge. I'd also be wary of using the word "quilt" on a customs tag as sometimes things marked "quilt" tend to walk away - I tend to describe things I send as "fabric wallhanging" or "textile picture" or something obscure (but still true) like that.
Any other customs questions, just ask and I will either answer them myself, google them or ask the relevant person what's best for their country. I know some of you don't do much international swapping - those of us outside the US tend to do more international swapping and may therefore be a little more experienced with the joys of international post, as so many of the quilters in the world are in the US! But I know that also there are several Yanks on this list who have organised big swaps themselves, and are probably much more knowledgeable than I am.
Wherever you are posting, you may wish to send your quilt registered or signature required - that's up to you; I don't want anyone to bankrupt themselves on postage, but personally, I do usually pay the little bit extra to send things like this "international signed for" - I think here it costs about £3 extra to require a signature at the other end - just makes me feel safer. In the US, I think the priority mail service is pretty good, and not hugely more expensive than first class post - it's been a long time since I posted anything in the US on a regular basis, so I'm not an expert, but again, I'm sure if you have questions, someone on the swap will know the answers.
As always, the best policy is, if you are unsure, just ask.