jetjets, making yoghurt is eaaaasy and cheap too. In Australia you can but an 'Easy yo' yoghurt maker for about £5 - I'm sure there would be something similar on line here. Its basicly a tub you put your starter culture (ie, some yoghurt) and warm milk in, then put the tub into an insulated bigger tub full of warm water and leave over night. You can make it without the insulated thing, but it gives more consistent results.