Three cascaded MXR Distortion Plus circuits in one pedal 31st January 2010
Using a quad opamp, you can cascade a few of these effects using very little board space. Only limits are what your ears can tolerate really, as three equates to absolutely tons of gain. If I were to make more of these (I probably won't, because I've no idea where to get more dual C500k pots, and they're quite expensive) I'd probably use a variety of different clipping diodes for variation.
Here's the component list and layout
Here's the PCB trace.
Ace demo by Peter Herman on Youtube here