inx3us: There are quite a few companies that make small SBC's (single board computers).
For example, look at the 5.25" Single Board Computers (Full-size Biscuit PCs) offerings from Advantech.
http://www.advantech.com/products/product_list.asp?category_name=Single%20Board%20Computers
These are 8"x5.75" boards and they usually have a on-board flat panel controller. Most of these companies provide BIOS's to support a variety of flat-panels (DSTN, TFT, EL, etc.). It is usually just a matter of buying a matching set of parts, building the correct LCD panel cable and flashing the correct BIOS. Finding the parts cheap is the real trick. I usually get my parts using a combination of eBay and computer surplus websites.
The only thing that I'm curious about is what you would have left after replacing the i-Opener motherboard and flat-panel. The i-Opener case? IMHO, this is the worst part of the machine, but I guess that others would disagree with me.
HTH
Glitch
Electronics run on smoke, if you let the smoke out they won't work