Christian at Cubist Effects as a new mod available. This mod is the Memory Boy Expression Mod. The Electro-Harmonix Memory Boy has an expression pedal option which controls the delay time or rate of modulation. Christian decided to provide the expression control as a knob vs. using a expression pedal. This will free up some space on the board. The knob is large, so you can still manipulate it with your foot.
Here is a video that Christian put together on this mod (cubisteffects on YouTube):