Signal duplication and join pedals?

Has anyone seen pedals that do this? I'm trying to set up some sort of twin isolated effect path that gets joined together.

Ive seen a/b boxes, but I'm looking to feed the same un effected instrument signal to two pedal chains simultaneously, and then combine the two different post-effects signals into one.

Ive seen a one control wet dry box that might work, anyone done this or have some idea how I might accomplish this?

 

Exactly what I'm looking for, and its only one pedal instead of two! Thanks