There is a nice little scene of companies in Espoo filled with some incredibily talented technologists who all got their start at Nokia.
Even if Nokia itself doesn't return, I expect at least one or two major technology developments out of there. I have my eye on ICEYE and have even thought of maybe working there.
Not Nokia, but yes I used to work for opera and trolltech was just a floor above us. We did a lot of work for Nokia device so maybe that’s what you were thinking of.
Nokia itself was a giant corporation with multiple buildings around Finland.
A few examples:
Nokia (the sleeping giant will awaken again :))
Nordic Semiconductor
The Qt Company
Unity Technologies
I might be influenced by living in Scandinavia. :)