If all you want is programmable macros, then something like the Nostromo or Orbweaver could serve you well; every button and each direction of the 8-way hat switch can be changed to any input or macro possible from a USB device, including mouse clicks, multimedia commands, launching programs, or changing its own settings.
If your typical workflow can be reduced to 15-230 macros that you can keep straight, it could replace the keyboard as a primary input device. If you would benefit from 15-20 macros that you need to take a hand away from the keyboard to execute, it could serve as a useful addition. If you just want a keystroke combination that executes a series of commands, that's probably better done in software.
Thus spake Eliezer:
It seems that many here might have outlandish ideas for ways of improving our lives. For instance, a recent post advocated installing really bright lights as a way to boost alertness and productivity. We should not adopt such hacks into our dogma until we're pretty sure they work; however, one way of knowing whether a crazy idea works is to try implementing it, and you may have more ideas than you're planning to implement.
So: please post all such lifehack ideas! Even if you haven't tried them, even if they seem unlikely to work. Post them separately, unless some other way would be more appropriate. If you've tried some idea and it hasn't worked, it would be useful to post that too.