I have recently used Segger's remote tunnel server a few times to good effect to troubleshoot devices in a field test site. It can be a challenge getting a person who is not familiar with Segger's tools to get the remote server software configured to use the tunnel (I plan to remedy that with some scripts). I have a couple J-Link units (actually a J-Trace and a Flasher) that have an Ethernet interface built in. It would be very useful if the unit could be configured so that when it detects an Ethernet connection that it automatically connects to a Segger tunnel server with some pre-configured parameters (the tunnel server name, name of the JTAG unit - default to the serial number, password).
That way as long as the person at the J-Link end of things can get an Ethernet connection, I (or whoever) could connect to that J-Link from wherever I happen to be with no other effort on the part of the person on the J-Link end of the connection (which might be a customer site for example). That user wouldn't even need a PC - just a USB power connection (maybe not even that in the case of the Portable Plus).
I'd think that for the J-Link WiFi in particular, this would be a killer feature.