Read somewhere this week that a major motherboard manufactuer is launching a motherboard which has flash memory (the type used in things in sd cards etc)
You can launch it so boots up in a version of Linux os with firefox and skype preloaded, or use as a normal pc (taking the normal time to boot off of hard disk)
At the moment the motherboard is not cheap, but they are talking about laptop versions and cheaper version early next year.
This should help reduce costs if all the pc is to be used for is browsing the web or communcation. No HDD, or windows operating system. These two are a major cost and may make it cheaper to run a simple pc in the future.
At the moment nothing to get excited about but with the cost of broadband getting cheaper in the uk and phill. It may soon be possible to have a lightweight, compact, low power cheap web 2.0 computer in either location.
Flash memory based laptops already exist, but trust me they cost a fortune but the difference is amazing