One side effect of having all the SAS flights out cancelled, including the one I was booked on at 8am to London, is that I spent a whole day in Arlanda airport. My laptop battery doesn’t survive that long, so finding at least one power outlet became a priority around 11am.
I found nowhere at all in terminal 5 where the power points were live, but a short walk into the Sky City area gets you to the East West cafe (towards the terminal 4 end of the area). This has a small seating area off the main walkway, at the back of which there was a power point that was live. Sky City has coverage for both Homerun and the Arlanda Airport wireless network, though at the back of the East West cafe the signals are pretty weak.
Going a little further, down the moving walkway/ramp into terminal 4, right in front of you is the Simply Coffee cafe/bar. This has power points under the bar seating around its outer edge, and also some on the sides of the columns where the sofa seating is. Down here, although I could see what Windows claimed to be strong signals from Homerun and the airport wireless, only the latter actually worked. I could not get associated to the Homerun network down here at all.
There were also a few more on the aircraft side of the security checks, though only the airport wireless service seems to be visible in the gate areas (despite finding a very prominent Telia access point hanging in the ceiling next to the gate I was leaving from.