Mix together the Rice Crispies, oatmeal and coconut--set aside.
Sift together flour, soda, powder and salt--set aside.
In a very large bowl, cream brown sugar, white sugar, butter, eggs and vanilla. Slowly add flour mixture to creamed mixture. Add oatmeal mixture and mix together. I use my hands (scrubbed first!) for this part--it's easier.
Drop by spoonful on cookie sheet. Bake at 350 for 10 to 12 minutes depending on your oven. If you like them soft.bake less.