I've just bought one of those old fashioned Desktop PCs, because I need something meatier than my ageing MacBook for working on photos and such. We currently just have laptops, on wifi. The desktop will be far away from the router.
a) Get a wifi card for the desktop, thus having to faff with drivers (doubly because I'm half thinking of hackingtoshing it)
b) Run a long cable through the house, possibly being shouted at by the Mrs in the process (The desktop has a gigabit network, not sure what the router has)
c) Try one of these fancy powerline connectors. Doesn't seem to offer much advantage over wifi, except I won't need drivers for the PC.