Dell/Razer "Chameleon" AT Keyboard
Some people may already be familiar with this, most notably through Razer's Star Wars The Old Republic offering, which has 10 of these keys on the device. Alternatively you may have heard of the amateur attempt several years ago called the Optimus Maximus keyboard - a product that sells for approximately 1,500 euros! However, bear in mind this product was made by an art studio, not a global, first-party computer manufacturer...
For the uninitiated, an AT (or "Adaptive-Tactile") keyboard is a device where every key on it incorporates an OLED screen. This means that when users want to use a program with its own keyboard functions, the default layout will disappear, replacing the surface of the keys with the application-specific layout. I cited this previously in M18x R2 thread and one of my own laptop ideas, though I now believe it should be a two-fold project for Dell.
My suggestion here would be to manufacture it first as a peripheral for desktops, and then examine if it can be integrated into laptop solutions. The manufacture of this item is not going to be cheap and, until it goes into mass production, neither will the price tag for the customer (possibly 150 euros); however, that doesn't mean it isn't a worthwhile product to pursue for development. The greatest companies to benefit from it will be Autodesk and Adobe, which both produce software suites with very different keyboard layouts to the standard MS Office work. After that will be the games studios, especially those who make MMOs that use macro keys for many of their specialist functions.
If Dell were to pursue this in conjunction with Razer, both companies' extensive R&D could succeed in making a product that is affordable, particularly since OLEDs are becoming gradually cheaper.