I'm considering another LaserOscope design. This project was featured on Hackaday: http://hackaday.com/2015/03/19/diy-oscilloscope-with-a-scanning-laser/
One interesting comment was: "What an incredibly complex way to do a simple task! A 32-bit computer with 512 MB of RAM and a multitasking operating system does nothing but blink an LED, which through an optocoupler and amplifier, drives a motor. This much could be done with a battery, a variable resistor, and a motor. And he didn’t just use a $30 Raspberry Pi, he used a $150 kit that includes an RPi for this task, in addition to at least $100 for Little Bits kit."
Yes, it is expensively over-engineered. The actual point of this build was to demonstrate optocoupling. There are much simpler ways to demonstrate optocoupling, but how often does one get the chance to build an analog oscilloscope out of a disparate pile of toys, however Rube Goldberg-esque, just for fun?