Returning back to universal sync mechanism idea posted almost a year ago Universal server storage and news about syncing Angry Birds saves, for the beginning it can be quite simple to organize one worldwide cloud service accessible from any OS and device where any application can store some data.

Example:
Application developer registers at superappstoragecloudservice.com and adds several applications.
Each application obtains its own GUID id and then implementation on any platform can access superappstoragecloudservice.com/appStorage// and store and retrieve settings, save files etc.
It's good idea to limit each app slot about small like 4 kilobytes per user not to allow content storage

New Lightpeak (Thunderbold) technology from Intel opens completely new horizons for external devices. Presenting the idea that can open new performance perspectives for laptops.

External box equipped with 4 (or better 8) RAM slots and hardware controller and interface board capable to access this RAM with almost no additional delays.
Box is connected with dedicated Lightpeak (Thunderbold) port on your laptop and is recognized by operating system by ordinary external disk but is used just as swap file storage for laptop's own RAM.

Due to page oriented (or even page cluster oriented) algorithms for swap file management transfer should be effective.

So you can have for instance 4 or 8 Gb of laptop's own RAM and up to 64Gb of backup RAM as swap. Pretty nice perspective and not so expensive even now.