Noboarding is basically riding on a snowboard that has no bindings. People who like it appreciate the truer "surfboard" feel, where it's the action of the feet and the riders balance that drives the board -- as opposed to forcing it through the attached feet. There is a Canadian group (www.noboard.ca) that manufactures a noboard plate which attaches to the top of the board, or you can buy a special version of the Burton Fish called "Nofish" which comes with that plate.
I wanted to see how it'd feel, and so I built a simple prototype. I used some leftover 1/4" thick rubber truck bed liner, binding screws from my TD2's, and I bought a few pipe clamps and a bungee-type strap with two carabiners. After 1/2 hour of assembly and about $5 in materials I had my own very simple noboard!

The noboard

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Lisa and I hiked up Monarch a week after the ski resort closed. The previous day it dumped over a foot of fresh snow, but we got there in pretty nice conditions. Here is a video we shot:
Snurfer? Noboard? Just have fun! from snowytom on Vimeo.
Next time I'd widen my stance, shorten the strap, and attach a leash. But it was a blast even with this simple assembly!