> I'll bet $10 it hasn't! That I can't send $10 from one country to another, without paying fees that are a significant proportion of that amount

I'd take you up on that bet! I'm not sure what an envelope costs, but probably less than $0.1 if you buy more than one, then add a stamp (usually around/below $1 in most places in the world AFAIK, even for international destinations).

Please send the $10 in an envelope to Oranjerie 114, 7311 WP Apeldoorn, Netherlands whenever you can :)

Ha! Fine, it will have to wait until I'm next near a post office with time to kill, otherwise it's not convenient. I think you'll allow that "not an unreasonable amount of effort" could imply "convenient".

I think the post offices where I am only sell the envelopes in bulk, and buying a pack will probably add an unreasonable 20% - 30% of the amount, but I'll concede that most people will probably have an envelope from a bank and a glue-stick lying around.

This is very off-topic, but sending something to an address which I can't tell is complete, without a name, has reminded me of something I find interesting.

A few years ago, my mother received a postcard from a friend who didn't have her address handy. She sent it with just my mother's name (first and last), the city, and country (New Zealand). It took some time, but it reached her! In NZ, "city" is used for some pretty small places - the population is only around 70,000. But I'm still very impressed with the effort to deliver that to her. Especially for a postcard - even internationally the postage on those is not a lot!

Sweden - Netherland: 3.6 euros to send a letter. Sure I could fit a couple of 500 euro bills there, but the point was that you cant send money with out paying too much.