I was touched by this and had never heard of it. Now, I am wondering what happened to the boxcar and contents that came to Alabama. edit-- Wait! here it is http://mercitrain.org/Alabama/ Merci Train - Home Page
I saw one of these a few years back. Not sure where it was now. We were doing "GeoCaching" and we were instructed to go to such and such location to find. The "Cache" has since been archived but I do remember there were a few of these scattered around the Country. I'll check and see if I can find something in the geocache archives.
I hadn't heard of this, either. I used the main website Jeff listed, and found this for Pennsylvania Merci Train - Pennsylvania Page There is a lot to be said for this. It goes to show that American largesse was remembered.