I don't have a secondary computer at the moment and have been using my Mini 9 for Skype while gaming with my aging Dell Dimension.
Last session we were playing on and off for most of the day!
I have been shutting off WiFi and using the Ethernet port to help reduce the amount of heat the wireless card generates over long periods since it's right on my desk next to the router when I'm doing this anyway.
To be honest I don't see any problems when I'm using it in this way, but one wonders if it ends up being hard on the system over the long term since you bring it up.
Inspiron Duo: Win7 Pro 32-Bit, Intel 6200 Wifi Upgrade
Former Inspiron Mini 9 Owner, Modder, Enthusiast