Gotten a few requests for this one. The Riot distortion from Suhr is built around 2, dual opamps (4580 in originals, but others can be used) with several clipping options for a great high gain experience. You can pretty much use whatever diodes you want, but it's laid out for 2 LEDs always clipping, with the option of adding either 3, 1N4148s in asymmetrical orientation or 4, 1N34s in series. You can also try replacing D4 with a 1N4148 (I've included pads for that on the PCB), or changing the color of the LEDs. Really, just experiment with what you have on hand and chose what sounds best to you.