1) Prepare a microphone or a recording device (preferably something stereo) on your desk.
2) Start recording.
3) Open a window.
4) Listen for 4 minutes 33 seconds. Don’t add anything!
5) Close the window.
6) Stop recording and send the soundfile to ‘jurgen [at] aifoon [dot] org’ (thru yousendit, or dropbox or whatever…)
7) Oh, and mention where it was recorded…