Here's a nifty product I stumbled across that might be of interest to guitar players. It's an adhesive backing for attaching stompboxes to a pedalboard. I'm thinking it might be of use to me as a keyboardist, as I have issues with my sustain pedal and effects footswitches walking away from me while I'm playing.
 
http://www.proaudiostar.com/stagetrix-pedal-fastener-3-pack.html?utm_source=ProAudioStar+Email+List&utm_campaign=7e4955c9a1-23_essentials_under_96_4_2015&utm_medium=email&utm_term=0_ed191e2895-7e4955c9a1-408435525
 

Godlyke Power-All PG-1M Power-Grip Pedal Mounting Tape  
 
http://www.musiciansfriend.com/amplifiers-effects/godlyke-power-all-pg-1m-power-grip-pedal-mounting-tape?rNtt=effects%20pedal%20tape&index=6
 
have used this stuff for years

you can see the tape on the pedalboard....
works great,
but over time, the glue on the hook and loop parts that you attach to the pedals,
can get a bit fluid, especially if exposed to heat.
 

I will take a look. Thank you for sharing. My pedals lift up from the board all the time

I prefer this method.  Even less room for movement.
 
 

That's clever! Better even than adhesives, because it's unaffected by heat or humidity, and it's un-doable if you change your pedal collection.
 
My current solution involves rubber placemats. It's a kind of rubber webbing. You can buy the stuff in a roll from the hardware store and cut it to size as needed.
 
I had originally discovered it as a way to keep plates and cups from sliding around when eating lunch on the boat. It can be laid beneath my sustain pedal when I have to set it on concrete or wood floors. The problem is that although it's got enough grip to keep your coffee cup from sailing off the table in moderate seas, it's not quite grippy enough to resist my foot.

Highest Olive that's so perfect.  Are those standard chain links or did you buy them somewhere?  
 
I've been fighting my pedal board for years and nothing I've tried is ideal. And I often add and delete pedals so super sticky Velcro always meant the whole thing would come off bottom and top. And like all the reviews say, nothing sticks to the rubber and some of my pedals have big knobby feet. 
And Velcro gets dirty and traps dust etc.  
Long time ago I had all Boss pedals and I found these longer screws with the same thread. So I attached the pedals to a piece of 1/8" fir plywood using these longer screws. Now I have all different brands and the screws are probably all different but I was seriously thinking of doing it again.
Having your pedals mechanically secured is the best solution. I was looking at these $300 pedal boards that have a metal mounting plate that look like you could drill holes in. But your solution will work brilliantly on a chunk of "free" plywood. I'm currently  using and old briefcase that I removed the hinges and added a second set of latches to. This is an old picture because I see there is no Velcro yet.  I've filled it up with 7 or more pedals now. These new mirco pedals are great as they take up very little room. 
 

 
 

Sustain and volume pedals have always been my bain, you are correct 'flipper, nothing will resist the almighty foot! I have chained my sustain to the legs of my rack, and it lies currently broken on the floor. The no-slip mat does work well for a short session, but I'm back to screwing them down into plywood!

I've been reluctant to bolt the sustain pedal down to a board for fear of raising it too high, which could put my foot in an awkward angle and cause fatigue. But I hit on a possible solution this morning: using 1/4" Plexiglas and extending it out far enough that I can rest my heel on it. That solves the height issue.
 
Now I just have to figure out how to keep the whole assembly from sliding around. Rubber feet would raise it up too high. I'm thinking there might be some kind of slotted rubber edging that could be glued to the edges of the Plexiglas, that might only raise it by 1/8" or so.
 
It'd be so nice to no longer have to search around for my pedals and footswitches.