For years I've thought that if I were a manufacturer of budget motherboards, I'd make a desktop board with four sodimm memory slots. Why? Because the world is awash in smaller capacity sodimms that people have pulled out of their laptops and which are essentially useless. No one wants them because nearly everyone is looking for larger capacity sodimms for those only two slots in a laptop. But four slots would not take up too much room even on an mATX board, if the slots could be mounted other than flat, and could use those otherwise unwanted memory sticks. For example in the current market, those would be 1G sodimms and a low end computer could be perfectly happy with 4G of ram.

Won't happen, but it would fit a niche.