If you've ever thought about building a flying saucer, the government recently declassified documents from their attempts in 1956 to test a workable prototype.
Contracting with Canadian aeronautical firm, Avro Aircraft Limited, "Project 1794" was supposed to be capable of vertical take-off and landing at a top speed of Mach 3 and Mach 4 with a maximum altitudinal height of 100,000 and range of 1,000 nautical miles.
Following their initial report, Avro asked for $3 million to complete the development and testing process ($26.6 million in today's dollars). Instead the government chose to allocate money towards a smaller and less complex prototype, the Avrocar.
The entire Avro report is now online for review at the National Archives and includes some pretty cool schematic drawings and project breakdowns. The project even had its own letterhead.