Stumbled across this one on FSB and thought it looked cool. It was designed by JD Barbato and is kind of a mashup between a Tone Bender MkII and a MkIII, with a BMP-style tonestack, with a switch changing the cap values in said tonestack. You can build it with all germanium transistors or use a combination of silicon and germanium:
I am currently using AC187 germaniums for Q1 and Q2 and a 2N5088 for Q3. Using the silicon 2N5088 removes some noise from the pedal, and adds a distinct, razory, compression to the sound which I prefer in my pedals. This combo also gives a nice ToneBender MKI type sound (ala Ziggy Stardust) when you invert the tone stack and roll back on the gain and butter a little.
The pedal also sounds good with the 2N5088's in Q2 and Q3, but is very hard edged. I have tried the 2N5088's in every position and in all combinations. The pedal doesn't work if all three are silicon.
With a 2N5088 in just the Q1 position the pedal sounds pretty much the same as if all three were germanium.