I've recently heard about something called Homeplug where an ethernet connection is established via electrical sockets. This sounds like the answer to my wifi problems - I have a D-Link router and the connection is constantly dropping, both to my HP wireless printer and to my second Mac that's connected via a USB adaptor.
I hear the NetGear Homeplug is the best one, but does it work with Apple Mac? If not, is there one that does?
I use the new Intel iMac as my main computer (currently connected via Ethernet to my D-Link router), with an HP Officejet 7410 all-in-one wireless printer, and an old indigo iMac wirelessly connected via USB adaptor.