Jon Stephenson von Tetzchner, then of Telenor Research (the Norwegian equivalent to Bell Labs), is your best bet. He is the cofounder of Opera Software, and is now the CEO. An OLD e-mail address for him (from that paper with the Multitorg screens) is Jon.Tetzchner@tf.telenor.no
. However, that dates back to 1995. I'm not even sure that the address would work at all, especially considering ping won't even attempt to ping tf.telenor.no (unknown host).
You could call Opera at +47 24 16 40 00 (AFAICT, that includes the country code - it's a call to Norway, though) - 9 to 5, GMT+1.
The old versions of Opera provide lots of insight into why current versions of Opera do what they do, IMO. BTW, it was around Opera 5 that they tried to go for the mainstream, and drastically changed their UI to be more friendly to users of IE and Netscape. BTW, Opera 7.5 does some things the way old 2/3/4.x did... See that new address bar+nav buttons thing that wasn't on 7.2x? Opera 2/3/4.x didn't do it to THAT extent, but it was much like it.
UserAgent: Opera/7.53 (X11; Linux i586; U) [en]
Don't be surprised by my UA flipping from Opera 7.5x Linux or Win, Netscape Communicator 4.8 Linux, Dillo 0.8.0, Mosaic 2.7b5 Linux, or Firefox 0.9 Win.