Typically an X48 chipset based mainboard will start at roughly 250 USD. The two chips the mainboard manufacturer has to purchase from Intel total up towards 90 USD alone. Pretty high-end gear for sure as Intel's X48 chipset brings support for the all new 1600 MHz FSB processors, two 16x PCI-E 2.0 slots, which you can use for ATI CrossFire, two ATI graphics cards and heaps of nice features.
I'll spill the beans already for today, you can pickup this product for 199 USD. And it even looks superb.