I'll say it again - the coolest thing about researching your family history is collecting live cousins!
With the help of those wonderful letters, Google, GenealogyBank.com and even the 1940 Census/stevemorse.org and a lot of luck, my cousin collection is HUGE!
I started planning a get together for this June for the descendants of this branch of my family that the boomerang letters have given so much insight into. It has grown so large that I split it off from my website to it's own! I still have a ton of docs to add, and a few new letters, but these things are truly never finished! Check out www.EnzFamily.net
I have located at least one descendant from each of my great-great grandfather's 5 siblings that came to the US and the same for his own 8 daughters, (two children of theirs are still living!) except one that has proven difficult (I'm not giving up!) Everyone I've contacted is very gracious, helpful and happy to share and receive info. I have learned so much!
We plan to have a day-long meeting, slideshow of photos and even Skype with the cousins in Germany that day. It is going to be amazing.