You don't need a desktop PC to run low-latency DDR3 memory tweaked with Intel's Extreme Memory Profiles. As it happens, both Kingston and OCZ have announced Intel XMP-certified 4GB DDR3-1066 kits with Intel's mobile Core 2 Extreme processors in mind.
Let's start with Kingston. The firm's KHX8500S3ULK2/4GX memory kit features two 2GB modules rated for operation at 1066MHz with 5-5-5-15 timings and a 1.5V voltage setting. This kit comes "pre-programmed with both JEDEC and XMP profiles," so while it should work out of the box with those settings in an XMP-capable notebook, it should also function with looser timings on a regular Centrino 2 system (assuming it can take DDR3 RAM, that is). Kingston quotes a suggested retail price of $212—almost four times the price of pedestrian DDR3-1066 kits.
As for OCZ, the competing memory vendor is also targeting Core 2 Extreme laptops with a 4GB OCZ3M1066XM4GK kit, which is rated to run at 1066MHz with 6-6-6-16 timings and 1.6V of juice. OCZ doesn't explicitly say so, but one would assume its 2GB XMP-ready modules also have regular SPD profiles for broader compatibility.
According to Intel, both the OCZ and the Kingston kits are certified for use on Flextronics' 17-inch W840 laptop. The system supports both dual- and quad-core Extreme Edition Core 2 processors, not to mention dual AMD graphics processors, Blu-ray, and a top display resolution of 1920x1200.