Following is the complete list of In-n-out Secret Menu
Animal Style" - bun is grilled with mustard, sauteed onions instead of raw, pickles, extra "special sauce" - [this can also be applied to fries (Note: I recently tried this on fries, but don't personally recommend it / Nov. 2, 2003)]
"Wish Burger" - no meat, i.e. veggie burger
"Protein Style" - lettuce wrapped around the burger instead of a bun for all of you who are in "The Zone"
Update 12/23/2003 - there is no such thing as "Old Fashioned Style" - originally I had this listed as "ketchup and mustard instead of the weird special sauce" but that is incorrect as a call from In-n-Out today revealed.
"Flying Dutchman" - two meat patties with two slices of cheese. that's it.
"Double Meat" - Double Double without cheese
"4x4" - 4 meat patties with 4 slices of cheese. Are you SURE you can eat that?
"2x4" - 2 meat patties with 4 slices of cheese for the fromage afficionado
"Grilled Cheese" - cheeseburger, sans meat
"Fries - well done" - get your fries extra crispy and brown the way you like them!
"Choco-Vanilla Swirl Shake" - just what it sounds like Note: this is not an official secrent menu item, but at most In-n-Out Burgers they will make it if asked for... 12/23/2003
"Neopolitan Shake" - a blend of chocolate, vanilla and strawberry shakes.
You can find more details at
http://www.zenlemur.com/innout.shtml