At LEAST 3 times a day.. maybe a few teasers in the middle.
I definately can't go without it for more than a few hours..... well I can, but I feel terrible.
Sometimes I wake up in the middle of the night & just need it.
My favourite place for it though is in the kitchen, on the table, my second favourite place is in bed, but I'll do it virtually anywhere if I have to do it. I refuse to do it in elevators though, or toilets.. yuck!