MSI's Winki is an instant-on Linux operating system on a special thumbdrive that plugs directly into select MSI motherboards. It'll be similar to Splashtop and Hyperspace, though Engadget reports it'll be more elaborate than those more tightly-designed examples.
This is cool, but more inspirational than must-have. I'd like to see something similar to this that works on any PC, simply by being plugged into the spare USB or SATA motherboard headers that practically every motherboard in the universe already has.
On the other hand, a tightly-integrated, vendor-specific hardware solution could mean that they've solved the core problem on instant-on operating systems: Windows can't load "in the background" while the instant-on system runs, unless it's being virtualized by it.