there was a mind shield in Apoc... would it be possible to add one in OpenXcom? (Or any kind of stat-boosting item, for that matter?)
it would be nice to have a mechanic that allows for an item to have a property "ModifyXY: <integer value>". yes, negative numbers, too: perhaps the mind shield would increase Psi Power, but decrease Psi Skill while equipped? would make sense to me.
maybe there could even be two "modify" properties: "ModifyWhileInInventory" and "ModifyWhileEquipped" - a mind shield in the backpack might still help, but a sniper scope would only work if held in the other hand (or something like that)
This would also open the door for a whole lot of RPG-like stuff, which might be interesting for total conversion mods... Sword of +5 Strength, anyone?
@WarBoy, what do you think?
As for the Mind Shield intself, I would suggest the following:
research on mind shield can start after having researched
Mind Probe. It would be an early-to-mid-game item that helps you fend off Psi attacks when you have not yet discovered a way to even screen for psi ability in your soldiers.
construction requires 1 Mind Probe per Mind Shield. you don't have complete understanding of the technology involved, but you are able to modify the circuitry of the Mind Probe to create some kind of "Psionic Static Noise". Maybe the fluff text could even mention that using the Mind Shield appears to give some soldiers a headache, while others are unaffected, hinting at latent psionic abilities.
the graphics would be very similar to the Mind Probe: perhaps the silvery orb with a part cut away, and some little LCD displays and LEDs added?