I am going to start the "Insanity" workout tomorrow, in the format of a new "class" at my gym. I have heard of it, but never done it. I am very VERY out of shape, haven't been to the gym in months, but once upon a time I did Xfit. Can anyone prepare me for the Insanity?

I think J. diesel is doing it, he started last month. I would PM him. He also posted some of the (insane!) workouts in the November fitness thread.

Btw, I loved your "mildly disturbed" comment

I personally have not done the Insanity program but I know several that have and I know it's not intended for beginners. My suggestion would to ease into an exercise routine if you are very out of shape and haven't been involved in a program for awhile. All gyms have personal trainers or at least staff that can give you an assessment and recommend a suitable work out.