I haven't had much of an opportunity to waste film recently, but did come across one of my dad's wartime notebooks and a recipe for a warm tone developer. I posted a detailed thread on the Articles board.
Basic formula, from April 1945
Sodium Sulphite, anhy 40 grains
Hydroquinone 7 grains
Potassium Bromide (K Br) 4 grains
Sodium Carbonate, mono ΒΌ ounce
Water to 10 ounces
Use Type 1 paper, give about 8 times the normal exposure and develop for about 3 minutes. Average negatives on contrast 2, without a ground glass in the printer, require about 16 seconds exposure.