Cybernetic Implants
So, you're a cyborg, but aside from all your skills and your neat MFD, what other perks are there? Well, implants are the best way to make use of your new cybernetic rig! Throughout System Shock 2, you'll encounter these small upgrades throughout the Von Braun and Rickenbacker, sometimes quite well hidden and other times in plain sight. Though they provide both fairly standard and more interesting effects depending on the type, they all require energy to keep charged, with the maximum charge increased based on Maintenance skill level. By default, you will be limited to a single implant, the O/S Upgrade, Cybernetically Enhanced, allows for a second implant slot.

Below, you'll find a list of them, descriptions of their effects, and an assessment of which are worth keeping.

BrawnBoost(TM) Implant BrawnBoost(TM) Implant
Description: Provides +1 Strength.
Assessment: One of the best implants, and found extremely early, behind a locked door on MedSci. Strength is an excellent stat, arguably the best in the game due to providing extra inventory space and melee damage. With one, or a pair, you won't need to raise Strength higher than 4 or 5, useful if you want the benefits of a high Strength without needing to invest Cyber Modules.

EndurBoost(TM) Implant EndurBoost(TM) Implant
Description: Provides +1 Endurance.
Assessment: Endurance is a fairly useless stat considering the low cost of healing, and you don't want to keep your Endurance, and the Hit Points that come with it, tied to an implant. By the time you find this implant on Hydroponics, it's almost obsolete. Save your Cyber Modules to boost Endurance if you need it, and your implant slots for something more useful.

SwiftBoost(TM) Implant SwiftBoost(TM) Implant
Description: Provides +1 Agility.
Assessment: Another quality implant, first encountered on Engineering, in the Cargo Bays. While Agility isn't the best stat, it's a good choice for a secondary investment, considering the benefits to accuracy and movement speed. This implant is especially useful due to the fact that you'll be conserving your Cyber Modules much more in the early game, and there are more important things to spend them at that time. Feel free to replace this later on, either with permanent upgrades or Psychogenic Agility.

PsiBoost(TM) Implant PsiBoost(TM) Implant
Description: Provides +1 Psi.
Assessment: This implant is best reserved for Psi characters, as the +1 Psi likely won't be significant enough for most others to consider keeping the implant equipped. However, Psi users need all the help they can get, and having one or two of these available will give a noticeable boost to one's psionic potential. Appropriately, it's found in Engineering, making it possible to get the most out of it right at the stage where Psi becomes more effective.

LabAssistant(TM) Implant LabAssistant(TM) Implant
Description: Provides +1 Research.
Assessment: Fantastic upgrade, because Research is a rather useless skill except for when it's absolutely required by the plot (during Hydroponics, where you'll first find this implant), or unless you plan to specialise in Exotic Weapons. You can completely ignore spending Cyber Modules on Research, and let LabAssistant(MT) do all the work for you.

ExperTech(TM) Implant ExperTech(TM) Implant
Description: Provides +1 Repair, Modify and Hack.
Assessment: You'll find at least one of these on Operations. If you don't mind swapping your implants out whenever you need to use a skill, ExperTech(TM) provides the best bang for your buck, raising three skills when most others only touch a single one. This benefit is offset by the fact that the skills it improves are all situational, so don't keep this equipped all the time.

WormMind Implant WormMind Implant
Description: Converts 25% of damage to Psi Points. Requires Research 3 (Cesium (Cs)).
Assessment: Reasonably useful, but more so for non-Psi users, as they'll have both the Psi Points and Psi Hypos to spare. Effectively this translates to extra armor, and that's never a bad thing. More efficient than converting all those Psi Hypos to Nanites with the Recycler.

WormBlood Implant WormBlood Implant
Description: Allows Worms to restore Hit Points, +10 per pile. Requires Research 4 (Copper (Cu)).
Assessment: Another "good to hang onto" implant. WormBlood can be found mid-game, around Hydroponics and Operations, and, as its description states, lets you eat Worms for health. Obviously there's no sense using this if you want to save those disguisting piles for Worm Clusters, and there's no reason to keep it equipped when not in use, but it will save you a few Medical Hypos and Kits.

WormHeart Implant WormHeart Implant
Description: Provides +100% toxin resistance, and heals +1 Hit Point every 30 seconds. Requires Research 5 (Cesium (Cs), Hasium (Hs)), causes 100% toxin level when removed.
Assessment: Found on the Command deck and later on the Rickenbacker, I initially shrugged it off as useless due to the high Research requirement and how late in the game one finds it. However, the value of its healing cannot be ignored, and it provides good protection against the Annelid Arachnids that seem to be everywhere in the late stages of the game. If you're playing on the highest difficulty, where Hit Points are significantly more limited, this implant takes on a whole new level of usefulness, as well. Still not the best ever, but worth considering if you have the Research skill. Just make sure it doesn't run out of charge, or you'll end up with a potenially deadly dose of toxins.