My current pedalboard does not include any effect. It's only a MIDI control system. The heart (or, shall I say, the brain) of the system is a Gordius Little Giant Module (LGM). It is connected to a Behringer FCB-1010 (whose chip has been replaced in order to turn it into a dummy slave for the LGM), a Boss FS-6 double-switch and three Boss FV-500H expression pedals (see the physical wiring diagrams on the right).
In the past, I tried many different MIDI foot controllers, all of them completely dumb (most of the time, at the pretext of being simple to use). The silliness probably culminated with the Yamaha MFC-10 that needed to be rebooted in order to change one or two configuration parameters! Just imagine doing that live...
The only really decent pedalboard was in fact the very first one that I owned a (long) time ago: the Digitech PMC-10. It was entirely programmable, any kind of double-sequence of MIDI events being assignable to any pedal (per bank), the first sequence being sent when depressing the pedal, and the second one at release time. You could for instance trigger a synth chord from your feet... This pedalboard was no doubt way ahead of its time. It didn't get the credit it deserved. I reckon, however, that it was a bit fragile, and at that time, all the programming was done from a tiny remote-control (no computer, no USB etc.) which was extremely cumbersome.
Today, the Gordius takes over. It finally allows me to get all the nice features of the PMC-10 back at my feet, with a modern technology and Human-Machine interface. Roughly, nothing of what you plug into it has a predefined behavior. Everything is programmable. It's the ultimate degree of flexibility.
Here are some additional resources.