Citizen of Nowhere was created with Inform and has IFID A2666B00-C25B-44DD-BC72-BE4E360E1B3E. To play a work like this one, you need an interpreter program: many are available, among them Zoom
for Mac OS X and for Unix; Windows Frotz or Windows Glulxe for Windows. The postcard was written by Andrew Plotkin and designed by Lea Albaugh.
Or you can play without downloading anything by following the 'Play In-Browser'
link, using the Quixe interpreter. You'll need to have Javascript enabled
on your web browser.