Cheers! Actually, that's kind of handy. Thanks
Here in Europe most likely would use the Skyscanner. There the trick that works for me is to choose a country or city rather than a specific airport. E.g. below I've picked London(any) airport to Berlin for the whole month. This works for me (not always flying back from the same place) ;)
RE: How To Find The Lowest Airfare In Under 1 Minute