One piece of cyberware that was never translated into 3rd edition was the Synthlink.
For those of you not familiar with it, the synthlink was like a highly specialized version of the remote control deck rigger headware, that instead of controlling drones, would control a bank of music synthesizers. The twist to it, was, that in addition to taking straight Direct Neural Interface control, the thing was also capable of translating body movements, such as dance or gestures, into command sets that'd drive the synthesizers. It could also be set up to take input keyed off of the position of the diaphram, vocal cords, and mouth, so that the user's singing could also be used to control the synths, resulting in music acompaniment that perfectly complements the vocal performance. A fairly complicated piece of cyberware, but esentially, all it is is a headware RCD coupled with a limited simrig to get the body/muscle position data, and a dedicated processor to convert the ASIST signals from the limited simrig into commands that the RCD can then transmit to the synthesiser banks.
It was also a implant that was highly utilized by the Rocker Archtype, which was responsible for much of the Big-Hair 80's goodness that permeated the early edition Shadowrun products. I know that the general consensus is that the Rocker Archtype has nothing to add to a well designed Runner team, but with the talk of the changes that Matrix 2.0 and it's "Augmented Reality" will bring to the system, I think the Rocker is a character type that's already been living in an "Augmented Reality" world for quite some time. After all a synthlink equipped rocker can get a drum line going with a tap of a foot and summon guitar chords with the wave of a hand, as opposed to being tethered by a cable hooked into one's datajack, drooling and comatose while trying to do one's thing like Riggers and Deckers have been up to this point. Fits in well with the "mobile digital wizard" concept.
And while some people will say that the Rocker Archtype is purely a product of the 80s, I think that current events have begun to justify how a Rocker would fit in with living on the fringes of society and doing quasi-illegal activities.
Right now, all your big corporate record labels are fighting the new technologies for music distribution that are coming out, because they stand to make a signifigantly smaller amount of money overall under new electronic methods of distribution, while at the same time, losing control over what material gets exposed to the public so they can regulate what has the potential to become a hit. On the flipside, many new independent artists are embracing the new tools to try and build a fanbase, thus inadverntly placing themselves in the line of fire when the big corporatations lash out at things like filesharing and independent netcasting "radio stations".
By Shadowrun's time, we know that nigh-unbreakable copy protection in place on prerecorded media, manufactured bands, and pop music written by computer program instead of the actual artistic talent of a human songwriter, are all comonplace. In other words, big buisness, and not the independent artist, won the war for the fate of the recording industry. An independent musician, struggling to make a name for themselves seperate of the industry, while not living as far on the edge of society and the law as your typcial shadowrunner, is definately in the same neighborhood.
I say that bringing the rocker archtype back for SR4, is the perfect chance to both bring back a nostalgic feel for those of us who remember the old editions, as well as further define the flavor of the updated gameworld. Bring the game back to it's (big, dyed hair) roots!