I've started hearing about Nazi UFOs in the '80s. It's a topic that never went away, and I'm sure disclosure will continue into the future.
There are few compelling evidence of this type of weapon being developed prior and during, and perhaps after the war. These are:
1. The report of unknown flying weapons allies called "Foo Fighters" that are disk shaped in nature.
2. An interview conducted by El Mercurio in Argentina with Admiral Byrd after the very peculiar expedition by the US Navy called "Operation High Jump" which involved over 4000 personnel in the Antarctic in which Admiral Byrd stated "In the next war, world will be menaced by a weapon that can fly from pole to pole in short amount of time.". The nature of this expedition was said to have been to probe the Nazi base in the Antarctic called "New Schwabland".
3. An U Boat containing a cargo of tobacco surrendered to Argentinean government after the war. They claimed that they were part of a convoy of U Boats that had orders to maintain strict radio silence, and (probably) as a result got lost and surrendered to the Argentinean government. How big would be the total load of such a convoy be if a single U boat can be dedicated to carrying just tobacco ? They left Christiansand in Norway, and was heading to an unknown destination in the southern hemisphere.
All of these can be verified as historic facts if you check the records.
This episode did a good job of compiling information pertaining to the Nazi's development of UFO type weapon.
If you consider that most so called "modern" weapons such as the cruise missile, and flying wing aircraft have their origins in Nazi technologies, it's not too far fetched to presume they might have been working on an even more advanced and outlandish technology during the war. The weapons that showed up during the war were years ahead in their concept, but was already a dated technology to the Nazis in terms of development by the time they showed up in the battlefield.
This episode of Ancient Aliens presents many of the rumors about Nazi UFOs that came to light in the past 10 years. While no conclusive evidence of existence of UFOs exists, the series puts serious effort into presenting the most recent information regarding UFOs. The research they did were pretty thorough, and are cut above anything that was done in the past. For their effort this series scores high in its production value.