Yes it is refreshing fundj but I don't feel like getting 'refreshed' today as it got so much colder around here!
Ayran is mostly for Aussie folks these days
Cuilidh, I had never heard of lassi before
I've just quick searched on wiki and yes, it does look similar
In traditional ayran there are no spices though
It is very basic with just yogurt, water and salt
I use yogurt also to prepare smoothie kind of drinks as you do
I really enjoy them too