Yes, I have been thinking about this for some time, too. Here are some technological items off the top of my head (based on B/X spells and magic items):
A.I.M. (Artificial Intelligence Matrix) (an intelligent swords, but best used for more complex systems like robots, mainframe computers, powered armor and vehicles)
Anti-Grav Belt (Boots of Levitation/Speed/Traveling and Leaping)
Antiseptic Spray (Cure Disease spell)
Auto-medic Kit (Ring of Regeneration)
Cold-Protection Suit ([item] of Cold Resistance)
Clone-growth Chamber (as Raise Dead spell, but requires Neuro-matrix Cube to upload brain)
Detoxifier Spray (Neutralise Poison spell)
Electromagnetic Scanner (Detect Magic)
Energy Dampening Baton (Rod of Cancellation)
Energy Dampening Field (Anti-Magic Shell spell)
Exoframe (Gauntlets of Ogre Power or Girdle of Giant Strength)
Extra Dimensional Storage Case (Bag of Holding/Devouring)
Fire-Protection Suit ([item] of Fire Resistance)
Flashlight (Wand of Light)
Freeze Ray (Wand of Cold)
Food Purification Oven (Purify Food and Water spell)
Forcefield Manipulator Gloves (Ring of Telekinesis)
Forcescreen Belt ([item] of Protection/Defense with Protection from Normal Missiles spell)
Forcescreen Emitter (Ring of Protection +1, 5’ radius with Protection from Normal Missiles spell)
Grapple Gun (Rope of Climbing)
Glow Cube (Light spell)
Holo-Screen Belt (Polymorph Self and Mirror Image spells)
Holo-Vid Set (Phantasmal Force spell)
Hover Bike (Flying Broom)
Hover Platform (Flying Carpet or Floating Disc)
Hydrostaic Boots (Ring of Water Walking)
Heat Ray (Wand of Fire Balls)
Med-pack (Cure Light Wounds spell)
Multi-band Senor Array (Wand of Enemy/Magic/Metal/Secret Door/Trap Detection)
Molecular Displacement Belt (Pass-Wall spell)
Neuro-scanner Jamming Device (Amulet vs. Crystal Ball and ESP)
Neuro-scanner Jamming Scope (Crystal Ball with ESP)
Neuro-matrix Cube (like Mirror of Life Trapping, but records the brain, to download into a clone body)
Neuro-manipulation Device (Helm of Alignment Changing)
Optical Camouflage Suit (Cloak of Invisibility)
Photon Absorbing Array (Darkness spell)
Rebreather (Water Breathing spell)
Remote Neuro-scanner Array ([item] of ESP/Telepathy)
Restraint Collar (Ring of Weakness)
Restraint Spay, Can of (Web spell)
Sleep Ray (Wand of Sleep)
Sonic Nullifier (Silence 15’ Radius spell)
Sonic Ray (Horn of Blasting and Drums of Panic)
Stun Ray (Wand of Paralysis)
Surgical Kit (Cure Serious Wounds spell)
Universal Translator Kit (Helm of Reading Languages and Magic)
Volt Ray (Wand of Lightning Bolts)
Water Distiller (Create Water spell)
X-Ray Scope (Ring of X-ray Vision or Crystal Ball with Clairaudience)
As for mutant races and monsters, you can find a lot of strange creatures in the old monster books and modules, especially
Find Folio and
B3: Palace of the Silver Princess (the original, recalled copy). For example, the iconic Displacer Beast was based on A. E. van Vogt's
Coeurl (from
Black Destroyer and
The Voyage of the Space Beagle), making it an alien creature.