Demonstration of a Lenovo ThinkPad X220 laptop with Intel's 320 solid state drive (SSD), resuming from sleep. This feature isn't limited to newer laptops -- many older and cheaper notebooks can resume this quickly as well, if the hard drive is replaced with an SSD. Nonetheless, the ability of a machine to wake instantly from sleep (a.k.a. "instant resume") depends on many hardware and software factors.
($1,200 for Lenovo's X1?! Ouch -- I'll stick with the cheaper ones.)