Forward: Personally, I like the idea that the planes use tech and modern equipment. However, I also believe that, while the Exemplars use high tech weapons and toys, that they should be highly stylized. Further more, I think that each cardinal plane deserves its own particular style. The Shotgun from Hades should not be the same as a shotgun made in Celestia or Logos.
Hell
Weapons
As a general rule, Hell favors rifles, shotguns, RPGs, and other large weapons over handguns and pistols.
Lemure: Lemures are usually outfited with remote controlled bomb collars, or other suicide equipement.
Imp: Imps prefer sutibly sized sniper rifles, usually with explosive bullets to add a little extra kick. Imp rifles almost always incorperate a serpent motif.
Spinnagon: Spinnagons are the primary operators and directors of Lemure kamikazi squads. They prefer shotguns moddified to fire their own spikes when pressed.
Barbazu: Barbazu wield large, underslung shotguns in combat, making judicious use of their Teleport without error to get into combat range. Barbazu shotguns are remniscient of the glaives that were once their favored weapons, having long stocks, and large, razor sharp blades protruding from above and below the gun's muzzle. These blades allow Barbazu glaives to function just like glaives if nessiary.
Kytons: Kytons, along with Erinyes, form the primary exeption to the rule that Devils do not wield pistols and handguns. Kytons prefer compact weapons, valuing size and handiness over sheer firepower.
Bezekira: Ill suited to wielding most modern weapons, Hellcats occasionally are fitted with bladed grafts to augment the damage of their claws.
Erinyes: Erinyes, along with Kytons, form an exeption to the rule that Devils do not wield handguns or pistols. Erinyes often dual wield SMGs or poweful pistols.
Osyluth: Osyluth tend to carry combat rifles. Osyluth weaponry tends to have a very Gigeresque quality, involving biomechinal shapes and bone white colorations.
Hamatulas: Hamatulas wield combat rifles. Hamatula weapons always include barbs, spikes and other sharp protrusions, remniscent of the barbs that grow from the Hamatulas body.
Gelgulon: Gelgulons favor powerful combat rifles and shotguns. Gelgulon weapons are often modular, with individual parts incorperating ridges and fitting togethor in such a way as to create the impression of overlaping plates, much like the overlaping plates of chitin that cover the Gelgulon.
Cornugon: Cornugons prefer to wield large grenade launchers, similar to the Brute Shot of Halo 2 fame.
Pit Fiend: Pit Fiends arm themselves as they see fit. Most prefer range or brute force. Pit Fiend equipment often seems as if it has been crafted from corrupt, vile flame. This is often precisely what it is made of.
Tech by Layer
Avernus: Technology on Avernus focuses primarily on industry and weapons production. Robotics feature heavily in the innumerable factories and production lines, and most automated systems have lemures and larva incorperated into the machinery.
Computers are all military devices, capable of assimilating tactical information and communicating orders with great efficiency.
Dis: Technology on Dis mimics the technology found in most prime cities.
Minaruous: Technology on Minaruous is geared towards mass production of consumer goods at the lowest possible price. This means that a great deal of production is done in massive sweatshopes and on huge assebly lines. Technology owned by the beaurocacies is always as showy and obviosly expensive as possible.
Phlegatos: Technology in Phlegatos is geared towards toture, vice, and temptation.
Stygia: Technology on Stygia focuses mainly on media, especially media that is designed to influence the observers opinions and thought processes.
Malboge: Technology on Malboge focuses on minning and resource extraction, as well as support and infrastructure. Stainless steel and rusty iron are common components of Malboge construction.
Maladomini: Technology on Maladomini is advanced, mainly in the fields of computers and architecture. All media is constrolled, and survielence technology is omnipresent.
Cania: Cania posseses the bleeding edge in almost all technological fields.
Nessus: Nessus has what it needs. Most technology in Nessus features a heavy biomechinal style (Check out the art of Giger to get a feel of Biomechinal).
Don't get me wrong, I like the Idea of the "Urban" or D20 "Modernized" version of Planescape... but... Why is everything so War-bent or Militaristic? If I'm in the wrong on this, please point that out (and why!), but Why is Hell so... like this? I mean, the original Baatorians were either cruel torturers or Deceptive lawyers (Let us not forget what Grenpoli served as...). Also, wouldn't many of the other planes be apptly opposed to violence, militarism, or the like? I mean - here you go and post about Maladomini being all 1984 like - but in truth - the layer was meant to be something entirely different - like a corrupt ACLU - not some Statist, gun-totting warzone runned by Big Brother. Well, I guess since this is all a work in progress, I recommend trying to compare the Planescape Planes of Law Box set with the D20 modern paraphenalia - at least to get a better understanding - because this needs work.. a lot of work.
Also, is just me or... does this person's interpretation of Minauros remind anyone else of Wal-Mart? I mean - I just went and watched the Frontline episode on Wal-Mart and... wow... Wally world is not just the Devil... its a layer of hell; isn't that ironic?