I know that recently everyone commented that there are problems with sending stuff through the postal service, but you can pick up a Global Priority Mail envelope at the post office that is a very good deal.
To Brazil it is $5, the envelope is big enough to fit photos, and a CD, and if you don't go over a pound, you don't need any customs declarations. The max you can put in the envelope is 4lbs.
Also, if you stay below 1 pound, you can mail it from your mail box.
I'm planning to test this out and see if it arrives. The convienience of getting 4 or 5 of these at a time then mailing it out over the next few months seems very good.