Laptop computers are becoming much more popular and will soon outnumber desktops if they don't already. However, a laptop is designed to be portable and therefore compromises are made. While a desktop keyboard has a number pad, most laptops do not in order to save space. Laptops are the primary tool of accountants who are often contractors required to be onsite at a clients location. The lack of a number pad is a disadvantage to these professionals.
Why not utilize the real estate on the touchpad to perform double duty as a number pad? This functionality could be toggled with a NumLock key somewhere on the laptop. This would maintain the portability of the laptop while vastly increasing the usability for most users (and not affecting the users who do not require this ability).
This feature is completely manufacturable and would basically be a software addition as well as marking painted onto the touchpad surface. The incremental cost to the manufacturer is negligable with respect to the value added to the customer.