Glen Akins build a USB Stack Light Controller based on PIC16F1459 and documents the process on this personal blog. He writes:
After using the PIC16F1459 to build numerous USB HID input devices including a giant keyboard, a tiny keyboard, and a big red button, it was time to see if the PIC16F1459 could be used to control outputs too. Sticking with the industrial theme, I chose to build a USB controller for a, um, stack of industrial stack lights.
[…]Now that the enclosure and PCB size were finalized it was time to design the electronics. One requirement was to be able to fade the stack lights in and out and control their brightness. The PIC16F1459 only has two hardware PWM channels though. To PWM three different colored stack light segments would require external hardware or some crafty software techniques. I decided to throw hardware at the problem.
USB Stack Light Controller based on PIC16F1459 – [Link]