I don't think it's a bug in SoftPerfect's Network Scanner because I can get the same results using two other port scanners.
Oddly, "Giga" is the only device that does not show as exposing 8080, yet it legitimatly exposes it for access to an IP cam server it runs. OTOH, that's the box that is running NetScan.
After a little Googling, I come away with something called "Squid" using 3128 and, I think, 8080 to somehow improve response over the LAN.
But I can't find any evidence of something called "Squid" running on my main PC. There's a Linux-powered NAS box (NAS_Port_1) on the LAN but I don't know enough to say for sure that Squid is not running on it. A post to the NetGear forum hasn't provoked any replies.
I looked at Control Panel | Internet Options | Connections | LAN Settings, but did not see anything in the way of a proxy.
I'm starting to get a little paranoid about this.
Can anybody shed some light?