A common indicator of futuristicness in games, movies, and tv shows is implanted technology. The most ubiquitous implants are usually radios/headsets, and full on computers integrated right into the brain to give an overlay of the internet. Often the ability to plug one's head into computers is displayed on occasion, either through jacks right in the skull/neck or through a proxy brain interface thing.
Somehow, I just don't see it happening. When I think of implanted radios, I can't help but think of all the times I've gone through places with weird electromagnetic characteristics, that cause headphones to squeal at max volume. Obnoxious if you can pull them out, significantly worse if they're embedded into your skull. Similarly, the possibility of undergoing brain surgery if one of the connecting wires from the implanted computer goes bad seems like a bit much (but is less of an issue once medical microbots/nanobots are available). The human body doesn't really possess much in the way of spare empty space up in the skull, so any computer would need a surgical operation to open up enough room to sit. It's a further surgery (possibly minor) to upgrade to this year's model, unless the implant socket is designed to allow them to be swapped as one might swap out a chip. Cyberbrains that make the entire brain readily removed and worked on without difficulties would make implanted tech more accessible across the board (be it prosthetics or just upgrades over the meat), but is of course its own significant can of worms.
Personally, if I were to get something done to make my headset more permanent, it would be a piercing. Put a hole right through the cartilage flush with the side of the skull. A simple, non-invasive, well known procedure, and makes the headset both sturdy and easily removed for privacy/repair/replacement.
There's one other category of implant that I WOULD actually trust, because they don't really go obsolete, or at not nearly the same rate as electronics. That would be weaponry and tools. One of my policies when building a character, and indeed going about my daily life, is to keep a knife handy at all times. Even still, it can be slow or difficult to access if you need it in a pinch. Why not get one built right into your hand? You'll always have it if you need it. Cyberguns are similarly readily available, although without substantial failsafe engineering they present significant possibilities for problems, as you point the gun embedded in your hand/arm at everything you interact with. Condition 2 or 3 on the gun would seem prudent at minimum, if not having them designed such that when not "active" the gun can't even go into battery.
Note that most of the downsides of implants are mitigated if they're implanted in chrome. If you've lost a limb, taken a severe injury that needed a bunch of repairs, or whatnot that can be done such that upgrades and changes are pretty readily accomplished (the device is built with standardized slots for tech and upgrades). Just like computers, if you plan to keep something for a while it's best to have parts easily swapped out.