If you haven’t realized, we do not have mirrors in SL. The reason is the rendering load they can add. If the Lindens added mirrors someone would add a fun-house mirror room. The region performance would likely drop to 1 frame per minute or possibly per hour.
But, we do have ways to fake mirrors. Those I’ve seen are awkward. But, this portal thing is one of the neatest mirror tricks I’ve seen in a long time.
You’ll have to turn the volume up to hear Adeon.
But, this is just way too neat. Be sure to give the video a thumbs up.