The coolest thing I've heard in quite some time...
Some of my favorite albums are those that capture those sounds from the atmosphere that we often miss and forget that it is another soundtrack to our life. Darrin Verhagen's Soft Ash and Alan Lamb's Night Passage come immediately to mind.
This is a collection - 4 CDs worth - of post World War II shortwave radio transmissions. There is a conspiracy, spy element to them which makes them all the more intriguing. You can read all about them here.
These are free on the archive.org website or you can find the recordings on the labels home page:Here
Speaking of Alan Lamb (which is how I stumbled across this in the first place), here is a mix of his "wire music" and some samples from the Conet Project:
P.S. Wilco's Yankee Hotel Foxtrot has its roots in these recordings and they were in fact sued by Irdial, the label behind the project.