This mount allows you to put 80/20 1010 extrusion into the mount. I am using it to make a spool holder.

Plus, having T slot on the printer gives me options for mounting more stuff.

I tweaked the Thing 770657 to make it fit the 1010 extrusion. Check his out if you like pipe for the mount.

I am using this with my 8020 braces and filament holder found here:

Braces
http://www.thingiverse.com/thing:868136

Filament holder
http://www.thingiverse.com/thing:868784

For mounting a 1kg filament spool from Hatchbox, I cut two 7" extrusions from 8020 [the 1010 size]
I then cut a 5 1/8" center top piece to go between the two vertical pieces.
I printed out some custom braces [coming soon] and a customized spool holder that mounts directly to the horizontal extrusion.

I will add the files once I verify everything is good.