This came out pretty good. I (almost) filled a 1qt mason jar with pasteurized whole milk and let it sit out until it reached room temp. Measured temp with a food thermometer was 76*. At that point I poured a little of the milk into a cup, mixed in powdered kefir starter (
this stuff), then poured the inoculated milk back into the mason jar and mixed well. Covered jar with coffee filter, using rubber band to keep the filter in place, and let it sit in a cupboard for 24 hours. After 24 hours, it's ready, so I removed the coffee filter, put a lid on the jar and refrigerated. Culturing time would be more or less, depending on ambient temperate (warmer = faster fermentation) and how much you want it fermented (go for a bit longer if lactose intolerant so that the lactose is fully broken down).
It smells and tastes quite a lot like yogurt; consistency is somewhere between milk and yogurt, so you would drink it, not eat it with a spoon.
I substituted the kefir for milk in a shake containing banana, eggs, protein powder and berries. Taste was somewhere between the taste of the shake with milk vs with milk and yogurt.
Since it tastes so much like yogurt, I'd bet it will go well with anything you usually pair yogurt with to sweeten/enhance the flavor; the difference being it would be a drinkable concoction rather than spoonable. So next I'll try blending kefir, frozen berries, powdered cinnamon and maybe a dash of cane sugar.