Deus Ex revolves around Adam Jensen who is a security officer in Sarif Industries - a company that invents and builds augmentation technology. After an alleged terrorist attack on one of Sarif's buildings, Adam is badly injured and the CEO of his company, David Sarif, orders surgical teams to implant mechanical augmentations into Adam. In fact, he orders more augmentations than are strictly necessary for Adam's survival so that he ends up being more augmentation than human flesh.
The game is quite open-ended in how you go about things, allowing social, stealth, technical, and combat (both lethal and non-lethal) resolutions to many of the challenges.
In some cases you can talk your way past an enemy through a tricky social combat system where you have to say the right things in order to get past them. If you choose enough of the right options, they will assist you. If you choose too many of the wrong actions, they may attack you or simply refuse to help.
Translating this into pen-and-paper isn't as hard as it sounds if you use a character's social skills to determine responses. In important conversations, simply use a system where players either pick one of several skills on their character sheet for use in a conversation OR the players converse with the person and you pick which one of their skills most apply to their current conversational strategies. If they choose the right option, good results happen. If they choose the wrong option, bad results happen. Have them roll the skill to either mitigate bad results or boost good ones.
As an nWoD example, say a player wants information out of a street thug NPC. He picks Intimidate as his skill, slams the NPC against the wall and threatens to smash both his knees if he doesn't give in. The player rolls two successes on a Strength or Presence + Intimidation roll. Unfortunately, Intimidate wasn't the right tactic to use on this guy as he instinctively rises to any aggressive challenge and meets violence with violence. Luckily, he mitigates some of the damage done by the wrong choice so the NPC merely swears at him rather than attacking or refusing to talk about it anymore. If the player had gained five successes, the NPC might have been so impressed that it counts as a success even if it was a bad tactic.
If instead, the player picked Socialize, he saunters up and offers the thug a smoke with a wry joke attached about the graffitti, and broaches the question he needs answered. The thug, not really giving a damn about keeping it a secret, is happy to start dropping hints about it. If the player makes a roll and gains two successes, then those hints are bigger. On an exceptional success, the thug is so charmed that he tells him outright or even helps out in some small way.
Alternatively, the storyteller could assign the roll based on the player's actions. The player who chooses to slam the thug against the wall is forced to roll Intimidate while one that offers a smoke and a smile is forced to roll Socialize. This is a good way to force players to raise the social skills they rely upon the most AND helps them realise what they're doing. Sometimes players can get confused and think they're being persuasive when they're actually being threatening and this can give them a wake up call, causing them to ask to try something different instead. If they request this BEFORE the NPC reacts, then I'd generally let them do that.
In Pathfinder, you'd generally use the Bluff, Diplomacy, and Intimidate skills though you might swap one out with an appropriate Knowledge check. In new World of Darkness, it could be any social skill, really.
In the videogame, if you get a special augmentation, you can see whether your current line of questioning is helping or hindering your efforts. You get a short personality profile of the target. You also get the opportunity to pick a special pheromone and line of reasoning that would work on an Alpha, Beta, or Omega personality. During the conversation, the target's own choice of words will be rated as either Alpha, Beta, or Omega, giving you further hints as to which category the target falls under.
Alphas are dominant, enjoy flattery, and will not suffer challenges well. Beta are neither overly dominant or submissive and simple reasonableness will often work. Omegas are submissive and suspicious of flattery but they are prone to obeying orders and dominant directions.
The Sense Motive (Pathfinder) and Empathy (World of Darkness) skills could give you an idea of whether it's successful or not. It certainly could be used to give players a basic personality template (such as Alpha, Beta, or Omega) to give them an idea of how best to approach people. It can also be used to give a bonus to your social rolls. I wouldn't make the player roll Empathy checks all the time but if they ask for one you could simply ensure you give out relevant information.
Okay, so that's just some ideas about using the social techniques to talk one's way out of difficulty. Now onto stealth. The same techniques for allowing Knock Outs and Stealth Kills that I mentioned in the Assassin's Creed Game Translation are relevant here. Also required is a cover system to help players bypass the enemy. Make sure to include plenty of well set up counters and unrealistically large vents for characters to make their way through. Electronic alarms and forms of surveillance also need to be hackable - perhaps by way of a remote-link-up palmtop that allows characters to use their computer skills. The enemy also shouldn't be too clever in their search patterns - at least not in your average area.
As for combat, this game uses a cover based combat system. Most systems make some form of allowance for using cover - whether miss chances or subtracting Durability from successes - so make sure you find out what the cover rules are and encourage their use. The easiest way to encourage it is to model it by having the first few enemies utilise cover constantly. In later sections you could have the enemy forget cover simply to speed up combats. Otherwise, be prepared for long and drawn out combat scenes as people keep missing each other.
You could use the system for upgrading augmentations by coming up with a game premise in a Cyberpunk world that says the characters are already riddled with such technology but that the tech can't be activated until their bodies become accustomed to existing switched on technology. How do bodies become accustomed to them? Through use and excitement, of course! Then just give them an experience point cost in the World of Darkness or add them to the character sheets at important points in the story.
Technical resolutions involve locking enemies in rooms, hacking gun turrets to attack the enemy, or perhaps dropping a crate on someone from afar. Also let them think tactically by throwing a ceramic dish to make a noise elsewhere to draw the enemy's attention - leaving them in a good position for a non-lethal take down.
A campaign based around Deus Ex, or including elements of it, would certainly appeal to all of the groups in equal measure. The Explorers would have a lot of fun getting excuses to go places they shouldn't, visiting other cities, and taking a peek under the cover of how a cyberpunk universe operates. Tacticians will love mixing up stealth with violence and will joyously hack turrets at all the right times to make the enemies scamper and sow confusion within the ranks.
Action Heroes will giggle with glee over the various toys and the chance to get up close and personal and basically be a badass augmented human. Investigators can be kept quite happy by the conspiracies and crime scenes and will ensure that there's at least some chance for the players to figure out who's the enemy before they die. The Communicators are still important due to how Deus Ex really makes conversation change the gameplay, the options, and the outcomes. In fact, communicators can really shine with the odd boss battle that is entirely social.
Funnily enough, you kind of need a group of very versatile players with this one as players that don't allow others their moments to shine will have problems. On the other hand, a lopsided party of Action Heroes, for example, will barrel through without so much as noticing the conspiracies or miss the tactical opportunities to really play up their cyberware. If you have less of a mix of types, it may be worth coaxing the Investigators to use violence or having your Communicator explicitly agree to dangerous mission objectives rather than expecting them to come to those conclusions on their own.
If you'd like to take a look at the trailer to learn more about it, you can check it out here. If you'd like to read the sort of tropes that Deus Ex used, you can find them here.
For the next Game Translation, you have a choice of these: Left for Dead, The Sims 3, Half Life 2, Prototype, Skyrim, The Last Express, Gears of War, Mass Effect, Realms of the Haunting, The Walking Dead, and pretty much any survival horror or horror game. If no one picks anything by next week, it'll be Prototype.
If you want to see the list of games I've done thus far, you can find the Game Translation series starter over here.