FFG Ross Watson said:
I should amend my statement above to say "any primitive ranged or close combat weapon." Why? Because the idea of mono-arrows and mono-throwing knives is just...well, COOL. 
and mono flintlocks! you just can't forget about mono flintlocks 
...i wonder why no player has ever asked for that one yet... 
from france
because shields armor are defensive weapons use in close combat the question still remain. as far as iam concern shileds and armore are more useful in close combat than in chess playing so are they eligible to be mono?
FYI. This has finally been officially answered.
new Errata 3.0, pg 8
The Mono upgrade on page 142 should read “Upgrades: Any
primitive close combat weapon.”
and
The Mono upgrade on page 142 should include the addition
“The Mono upgrade can be applied to a power weapon, but it has
no effect when the power fi eld is active. If the power fi eld is ever
lost or deactivated, the Mono upgrade’s bonuses will then apply.”
So, no chainsword or other non-primitive weapon getting mono ... except a power sword.
Also, mono no longer applies to arrows or primitive ranged ammunition (since they are not close combat weapons)
I would rule that manstopper ammo could then be applied to arrows, bolts for crossbows, and flint ammo. I would also include manstopper ammo is no longer primitive, but the ammo is not reusable.
Otherwise I would still allow the arrows, bolts and flint ammo to be mono. I just think it allows for characters who don't want to stick with las,sp, and other more advance weapons a chance.
from the errata:
The Lathe Blade (Weapon Upgrade) description on
page 147 should include the addition: “This upgrade
cannot be combined with the Mono upgrade.”
how do you make a lathe blade mono?
hit it on a rock a few times to dull the edge 
You can Mono a Powerblade but the mono will only have effect when the power field is turned off.
Normal Power Blade 1d10+5 E, Pen 6
power field off 1d10R, Pen 0, Primitive
now for the mono powerblade...
Mono Power Blade 1d10+5 E, Pen 6
powerfield off 1d10R, Pen 2
Powerfields can be noisy and lights up the night sky...
from france
any primitive wepons can be monoed? i'am surprise it means that a ligthning gauntlet can be monoed? it will be far better weapons with this enhancement. something perfect fro my pet project for my tech loving arbites
yes...it can be mono-ed