E,
I am pretty sure one of the kitchens that used Tidaholm did that. Hmm, I can't tell what they used for the bottom drawer under the double ovens, but here is the thread:
http://www.ikeafans.com/forums/progr...light=tidaholm
The same person wrote a mod about putting a lot of drawers into a tall cabinet - that may help with placement of the rails for the drawer:
http://www.ikeafans.com/forums/modif...ification.html
I'm planning to do a similar thing - put a deep drawer under a wall over, then cut back the upper part of the cabinet to wall cabinet depth, put in a shelf for a microwave and doors above. I want the top of the wall over to be 6-9" above counter height and the microware not as high as using a regular microwave cabinet would place it, so this seems the easiest way.
Anne