Optifast
I bought mine on Thursday last week. 3 weeks of Opti was $298. I am mixing mine with water only. You are only allowed 20 calories per day and I use that for my skim milk in my decaf coffee. I have only had 2 today and so far, it's not so bad. I got the vanilla so I can mix some flavours in with it if I get sick of vanilla.
You can mix it with cold decalf coffee, add syrups, baking extracts, unsweetened cocoa. Could try cold decalf tea if you want. Check out: http://www.obesityhelp.com/group/ontario_recipes/discussion/
There is a thread there called surviving Opti.
Cathy