Star Trek: 11 Incredible New Technologies That Were Immediately ABANDONED

7. Interphase Cloaking

Though both the Romulan Star Empire and Starfleet experimented with interphase cloaking, the technology seemingly was abandoned very early on. For Starfleet's example, that's understandable. Everything in connection with the experiment was a violation of the Treaty of Algeron, so they simply couldn't continue with the experiment.

What, then, for the Romulans? An Empire so concerned with maintaining secrecy - and employing a wide network of spies - would surely jump at the chance to master this incredible technology. So, what happened?

Introduced in The Next Phase, the interphase cloaking device served a dual purpose. It turned its subjects invisible but it also rendered them intangible, allowing them to pass through everything except the floor. This may have been an extrapolation of an earlier technology in use during the 2320s aboard the Space Station Baraam, though it certainly owed a lot to the device stashed aboard the USS Pegasus.

It's a little hard to believe that the Romulans simply gave up their research on this technology following the accident aboard their science vessel so this may be a case of the simple fact that you haven't heard anything more about it...means it's working perfectly.