I ran across this guitarheads site today, they have some interesting mods. The "Underdrive" caught my attention. Searched our forums and nothing came up. It looks to be a passive gain boost, somewhere in the realm of an OD pedal. It would be nice to have that control right on the guitar, and seeing how i never use my tone knob, i'm kinda interested. The main thing i had in mind is tube screamer like boost on top of my OD channel, or maybe adding a little dirt to the cleans on demand. Anyone tried/heard about this?