4 c  Lowfat or skim milk

    1/4 c  Nonfat dry milk (optional)

      2 tb Fresh yogurt

  Pour the milk into a quart glass container.  If you want to add nonfat dry
  milk to make the yogurt "creamier" now's the time.
  Heat in microwave until the milk reaches about 175 degrees.  (Takes about
  9 minutes.)

  Remove from microwave and cool until the milk reaches about 100 degrees.
  Add two tablespoons active yogurt.  Stir well, a whisk is good.
  Cover with plastic wrap.  Wrap in a towel.
  Replace bowl in microwave.  Heat on low about 30 seconds.
  Heat on low 30 seconds every 30-60 minutes for about 4 hours.
  You'll have yogurt.
  If you walk away all day but leave it nice and warm, it'll turn into
  yogurt, too, but will take longer.  And since you won't be there, you won't
  notice. Refrigerate and laugh at Dannon's high prices.