Several keyboards available already see programmable keys in addition to the standard 101-104 setup. You can custom assign a program to launch with the software included. Other programming would allow assigning various keys within the program itself to specify tasks.
For simply using a standard keyboard you would most likely need a go between since the main function keys are already reserved. A combination of more then one key could be written to see macros launched. That would be a basic instruction added into the programming.