A simple, effective machine which works. Our yoghurt maker arrived yesterday. I pre-warmed it for a few minutes, popped 2 tsp live plain yoghurt in the bowl, added 1 litre room-temp UHT skimmed milk (it fits), mixed, put the lid on and promptly forgot about it. The next morning, 17 hours later: lovely yoghurt. There was a little whey on the top, normal when incubated for this length of time - increase in acidity/tartness. Mixed the whey back in, and chilled. Made some lemon sauce, cooled. Combined the two. Result? Delicious lemon yoghurt.