I'm really enjoying mine ManicMum.
I usually have a glass in the morning, or pour it on my cerial (it's very filling), and both Mum and I have noticed that we feel a bit slimmer and 'better in ourselves', which may be because we feel less bloated.
I did start to feel a bit 'kefired out', so I used some to make Greek yoghurt (much easier than having to pre-heat the milk and keep it at the right temperature, as kefir ferments at room temperature).
Now I'm into a routine where I make enough for a few days and store it in a container in the fridge. I then put the grains in some milk in the fridge (the fermentation slows right down) until I need them again.
Some people make smoothies with it, but I understand it's possible to also make probiotic cheese, butter or use it as a sourdough starter.
I'm now going to buy some water kefit grains for my niece, as she's not a huge dairy fan, and while it's possible to use the milk grains with coconut milk, it's not ideal.
And yes Grinling, dogs apparently enjoy kefir (particularly the excess grains).