Here's mine, which needed to be small to fit in a Corvette, so...
Gokko/Soyan 12" X 18" aluminum pedalboard (with cheap soft case only $60).
TC Mic Mechanic (vocal).
Custom Tube Preamp (passive pups hitting a real custom biased tube for warmth/presence and feel, though the FM3's Amp Block is providing all tone shaping and gain staging).
Behrringer Wired IEM Headphone Amp (no worries about interference or dead batteries, and I'm not going to be jumping off drum risers, too old LOL!).
Custom Patchbay (to save the FM3's connectors from people tripping on cables on blacked out stages!).
The whole pedalboard complete with DIY patchbay and cabling cost around $100 (with cheap soft case), including clockable XLR's and right-angle MIDI connectors, D-Series punched project box, plus the D-Series 5-Pin DINs and XLR connectors, and the D-Series1/4" connector.
The FM3's FAS Link connector is powering the TC, Tube Pre, and Behrringer (total < 650ma @ 12V).
There is also a Mosky Dual Switch that will be dual-locked to the CEBA Screen Protectors assuming they ever ship, right above FC3.
UPDATE: Just got the CEBA shipping email, thanks CEBA!
FC Setup...
FC1 tap controls the Ableton LIVE Looper Plugin's Play Button, and hold the FM3's Tuner.
FC2 tap controls the Ableton LIVE Looper Plugin's Undo Button (PANIC!), and hold Ableton LIVE's Session Loop Button.
FC3 tap increments through the Scenes, and hold switches FX.
The Mosky Dual Switch taps select Auto-Wah and a Big Delay/Hold FX.
Everything else is automated.
Just an example of a non-standard usage, and thanks to FAS for making the FM3 not only sound so good, but also making it be so versatile routing and controller-wise!